diff --git a/client/Makefile b/client/Makefile
index ed4e550ff..1f857e584 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -55,8 +55,9 @@ ZLIB = $(OBJDIR)/libz.a
 
 LIBS = -I$(LUALIBPATH) -I$(MBEDTLSLIBPATH) -I$(JANSSONLIBPATH) -I$(CBORLIBPATH) -I$(ZLIBPATH) -I$(REVENGPATH) -I$(AMIIBOLIBPATH) -I$(HARDNESTEDPATH) -I$(CLIPARSERPATH)
 INCLUDES_CLIENT += -I./src -I../include -I../common -I../common_fpga $(LIBS)
-CFLAGS ?= -Wall -Werror -O3
-#CFLAGS ?= -Wall -Werror -O3 -Wchar-subscripts -Wundef -Wshadow -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Wredundant-decls -Winline -Wformat -Wformat-security -Winit-self -Wmissing-include-dirs -Wmissing-prototypes -Wstrict-prototypes -Wnested-externs -Wmissing-declarations
+#CFLAGS ?= -Wall -Werror -O3
+CFLAGS ?= -Wall -Werror -O3 -Wchar-subscripts -Wundef -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Winline -Wformat -Wformat-security -Winit-self -Wmissing-include-dirs -Wstrict-prototypes -Wnested-externs -Wmissing-declarations
+#  -Wshadow -Wmissing-prototypes -Wredundant-decls
 #  -Wbad-function-cast -Wextra -Wswitch-enum -Wold-style-definition
 
 # We cannot just use CFLAGS+=... because it has impact on sub-makes if CFLAGS is defined in env:
diff --git a/client/deps/amiitool/amiitool.c b/client/deps/amiitool/amiitool.c
index b63222d50..d7cd08351 100644
--- a/client/deps/amiitool/amiitool.c
+++ b/client/deps/amiitool/amiitool.c
@@ -15,7 +15,7 @@
 
 static char *self;
 
-void amiitool_usage() {
+void amiitool_usage(void) {
     fprintf(stderr,
             /*"amiitool build %i (commit %s-%08x)\n"*/
             "by Marcos Del Sol Vives <marcos@dracon.es>\n"
diff --git a/client/deps/cliparser/cliparser.c b/client/deps/cliparser/cliparser.c
index 1845aff29..27b0ed050 100644
--- a/client/deps/cliparser/cliparser.c
+++ b/client/deps/cliparser/cliparser.c
@@ -143,7 +143,7 @@ int CLIParserParseStringEx(const char *str, void *vargtable[], size_t vargtableL
     return CLIParserParseArg(argc, argv, vargtable, vargtableLen, allowEmptyExec);
 }
 
-void CLIParserFree() {
+void CLIParserFree(void) {
     arg_freetable(argtable, argtableLen);
     argtable = NULL;
 
diff --git a/client/src/aidsearch.c b/client/src/aidsearch.c
index 676db4cc7..291d2035c 100644
--- a/client/src/aidsearch.c
+++ b/client/src/aidsearch.c
@@ -13,7 +13,7 @@
 #include "fileutils.h"
 #include "pm3_cmd.h"
 
-int openAIDFile(json_t **root, bool verbose) {
+static int openAIDFile(json_t **root, bool verbose) {
     json_error_t error;
 
     char *path;
@@ -42,7 +42,7 @@ out:
     return retval;
 }
 
-int closeAIDFile(json_t *root) {
+static int closeAIDFile(json_t *root) {
 
     json_decref(root);
     return PM3_SUCCESS;
@@ -71,7 +71,7 @@ int AIDSearchFree(json_t *root) {
     return closeAIDFile(root);
 }
 
-const char *jsonStrGet(json_t *data, char *name) {
+static const char *jsonStrGet(json_t *data, const char *name) {
     json_t *jstr;
 
     jstr = json_object_get(data, name);
@@ -88,7 +88,7 @@ const char *jsonStrGet(json_t *data, char *name) {
     return cstr;
 }
 
-bool aidCompare(const char *aidlarge, const char *aidsmall) {
+static bool aidCompare(const char *aidlarge, const char *aidsmall) {
     if (strcmp(aidlarge, aidsmall) == 0)
         return true;
 
diff --git a/client/src/aidsearch.h b/client/src/aidsearch.h
index 00d2b134a..528146766 100644
--- a/client/src/aidsearch.h
+++ b/client/src/aidsearch.h
@@ -23,6 +23,6 @@ int PrintAIDDescriptionBuf(json_t *root, uint8_t *aid, size_t aidlen, bool verbo
 json_t *AIDSearchInit(bool verbose);
 json_t *AIDSearchGetElm(json_t *root, int elmindx);
 bool AIDGetFromElm(json_t *data, uint8_t *aid, size_t aidmaxlen, int *aidlen);
-int AIDSearchFree();
+int AIDSearchFree(json_t *root);
 
 #endif
diff --git a/client/src/cmdhf.c b/client/src/cmdhf.c
index ea5472c9d..ff2a5e79f 100644
--- a/client/src/cmdhf.c
+++ b/client/src/cmdhf.c
@@ -44,7 +44,7 @@
 
 static int CmdHelp(const char *Cmd);
 
-static int usage_hf_search() {
+static int usage_hf_search(void) {
     PrintAndLogEx(NORMAL, "Usage: hf search");
     PrintAndLogEx(NORMAL, "Will try to find a HF read out of the unknown tag. Stops when found.");
     PrintAndLogEx(NORMAL, "Options:");
@@ -53,7 +53,7 @@ static int usage_hf_search() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_sniff() {
+static int usage_hf_sniff(void) {
     PrintAndLogEx(NORMAL, "The high frequence sniffer will assign all available memory on device for sniffed data");
     PrintAndLogEx(NORMAL, "Use " _YELLOW_("'data samples'")" command to download from device,  and " _YELLOW_("'data plot'")" to look at it");
     PrintAndLogEx(NORMAL, "Press button to quit the sniffing.\n");
@@ -69,7 +69,7 @@ static int usage_hf_sniff() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_tune() {
+static int usage_hf_tune(void) {
     PrintAndLogEx(NORMAL, "Continuously measure HF antenna tuning.");
     PrintAndLogEx(NORMAL, "Press button or Enter to interrupt.");
     PrintAndLogEx(NORMAL, "Usage: hf tune [h] [<iter>]");
diff --git a/client/src/cmdhf14a.c b/client/src/cmdhf14a.c
index 7d2178c89..4e4e411e8 100644
--- a/client/src/cmdhf14a.c
+++ b/client/src/cmdhf14a.c
@@ -1261,7 +1261,7 @@ typedef enum {
 } nxp_mifare_type_t;
 
 // According to NXP AN10833 Rev 3.6 MIFARE Type Identification, Table  6
-int detect_nxp_card(uint8_t sak, uint16_t atqa) {
+static int detect_nxp_card(uint8_t sak, uint16_t atqa) {
     int type = MTNONE;
 
     if (sak == 0x00) {
@@ -1355,7 +1355,7 @@ const uidname uidmap[] = {
     {0x00, 0x00, "None"}
 };
 
-void getTagLabel(uint8_t uid0, uint8_t uid1) {
+static void getTagLabel(uint8_t uid0, uint8_t uid1) {
     int i = 0;
     while (uidmap[i].uid0 != 0x00) {
         if ((uidmap[i].uid0 == uid0) && (uidmap[i].uid1 == uid1)) {
diff --git a/client/src/cmdhf14b.c b/client/src/cmdhf14b.c
index 859df4a23..7be829472 100644
--- a/client/src/cmdhf14b.c
+++ b/client/src/cmdhf14b.c
@@ -684,7 +684,7 @@ static bool HF14B_Std_Reader(bool verbose) {
 }
 
 // test for other 14b type tags (mimic another reader - don't have tags to identify)
-static bool HF14B_Other_Reader() {
+static bool HF14B_Other_Reader(void) {
 
     // uint8_t data[] = {0x00, 0x0b, 0x3f, 0x80};
     // uint8_t datalen = 4;
diff --git a/client/src/cmdhffelica.c b/client/src/cmdhffelica.c
index dc3b07a1b..9757e54a3 100644
--- a/client/src/cmdhffelica.c
+++ b/client/src/cmdhffelica.c
@@ -123,7 +123,7 @@ static int usage_hf_felica_request_response(void) {
     return PM3_SUCCESS;
 }
 
-static void print_status_flag1_interpretation() {
+static void print_status_flag1_interpretation(void) {
     PrintAndLogEx(NORMAL, "\nStatus Flag1:");
     PrintAndLogEx(NORMAL, "  - 00h : Indicates the successful completion of a command.");
     PrintAndLogEx(NORMAL, "  - FFh : If an error occurs during the processing of a command that includes no list in the command packet, or if "
@@ -133,7 +133,7 @@ static void print_status_flag1_interpretation() {
                   "indicating the location of the error.");
 }
 
-static void print_status_flag2_interpration() {
+static void print_status_flag2_interpration(void) {
     PrintAndLogEx(NORMAL, "\nStatus Flag2:");
     PrintAndLogEx(NORMAL, "  - 00h : Indicates the successful completion of a command.");
     PrintAndLogEx(NORMAL, "  - 01h : The calculated result is either less than zero when the purse data is decremented, or exceeds 4"
@@ -167,7 +167,7 @@ static void print_status_flag2_interpration() {
     PrintAndLogEx(NORMAL, "  - C2h : Command is disabled already: This is the error that occurs in issuance commands.");
 }
 
-static void print_block_list_element_constraints() {
+static void print_block_list_element_constraints(void) {
     PrintAndLogEx(NORMAL, "       - Each Block List Element shall satisfy the following conditions:");
     PrintAndLogEx(NORMAL, "              - The value of Service Code List Order shall not exceed Number of Service.");
     PrintAndLogEx(NORMAL, "              - Access Mode shall be 000b.");
@@ -177,22 +177,22 @@ static void print_block_list_element_constraints() {
     PrintAndLogEx(NORMAL, "              - Block Number shall be in the range of the number of Blocks assigned to the specified Service.");
 }
 
-static void print_number_of_service_constraints() {
+static void print_number_of_service_constraints(void) {
     PrintAndLogEx(NORMAL, "       - Number of Service: shall be a positive integer in the range of 1 to 16, inclusive.");
 }
 
-static void print_number_of_block_constraints() {
+static void print_number_of_block_constraints(void) {
     PrintAndLogEx(NORMAL, "       - Number of Block: shall be less than or equal to the maximum number of Blocks that can be read simultaneously. "
                   "The maximum number of Blocks that can be read simultaneously can differ, depending on the product being used. Use as default 01");
 }
 
-static void print_service_code_list_constraints() {
+static void print_service_code_list_constraints(void) {
     PrintAndLogEx(NORMAL, "       - Service Code List: For Service Code List, only Service Code existing in the product shall be specified:");
     PrintAndLogEx(NORMAL, "              - Even when Service Code exists in the product, Service Code not referenced from Block List shall not be specified to Service Code List.");
     PrintAndLogEx(NORMAL, "              - For existence or nonexistence of Service in a product, please check using the Request Service (or Request Service v2) command.");
 }
 
-static int usage_hf_felica_read_without_encryption() {
+static int usage_hf_felica_read_without_encryption(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Use this command to read Block Data from authentication-not-required Service.");
     PrintAndLogEx(NORMAL, "       - Mode shall be Mode0.");
     print_number_of_service_constraints();
@@ -215,7 +215,7 @@ static int usage_hf_felica_read_without_encryption() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_write_without_encryption() {
+static int usage_hf_felica_write_without_encryption(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Use this command to write Block Data to authentication-not-required Service.");
     PrintAndLogEx(NORMAL, "       - Mode shall be Mode0.");
     print_number_of_service_constraints();
@@ -234,7 +234,7 @@ static int usage_hf_felica_write_without_encryption() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_request_system_code() {
+static int usage_hf_felica_request_system_code(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Use this command to acquire System Code registered to the card.");
     PrintAndLogEx(NORMAL, "       - If a card is divided into more than one System, this command acquires System Code of each System existing in the card.");
     PrintAndLogEx(NORMAL, "\nUsage: hf felica rqsyscode [-h] [-i]");
@@ -246,7 +246,7 @@ static int usage_hf_felica_request_system_code() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_reset_mode() {
+static int usage_hf_felica_reset_mode(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Use this command to reset Mode to Mode 0.");
     print_status_flag1_interpretation();
     print_status_flag2_interpration();
@@ -261,7 +261,7 @@ static int usage_hf_felica_reset_mode() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_request_specification_version() {
+static int usage_hf_felica_request_specification_version(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Use this command to acquire the version of card OS.");
     PrintAndLogEx(NORMAL, "  - Response:");
     PrintAndLogEx(NORMAL, "    - Format Version: Fixed value 00h. Provided only if Status Flag1 = 00h.");
@@ -283,7 +283,7 @@ static int usage_hf_felica_request_specification_version() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_authentication1() {
+static int usage_hf_felica_authentication1(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Initiate mutual authentication. This command must always be executed before Authentication2 command"
                   ", and mutual authentication is achieve only after Authentication2 command has succeeded.");
     PrintAndLogEx(NORMAL, "  - Auth1 Parameters:");
@@ -311,7 +311,7 @@ static int usage_hf_felica_authentication1() {
     return PM3_SUCCESS;
 }
 
-static int usage_hf_felica_authentication2() {
+static int usage_hf_felica_authentication2(void) {
     PrintAndLogEx(NORMAL, "\nInfo: Complete mutual authentication. This command can only be executed subsquent to Authentication1"
                   " command.");
     PrintAndLogEx(NORMAL, "  - Auth2 Parameters:");
@@ -551,7 +551,7 @@ static bool check_last_idm(uint8_t *data, uint16_t datalen) {
  * @param wr_noCry_resp frame in which the response will be saved.
  * @return success if response was received.
  */
-int send_wr_unencrypted(uint8_t flags, uint16_t datalen, uint8_t *data, bool verbose, felica_status_response_t *wr_noCry_resp) {
+static int send_wr_unencrypted(uint8_t flags, uint16_t datalen, uint8_t *data, bool verbose, felica_status_response_t *wr_noCry_resp) {
     clear_and_send_command(flags, datalen, data, verbose);
     PacketResponseNG resp;
     if (!waitCmdFelica(0, &resp, verbose)) {
@@ -1464,7 +1464,7 @@ static int CmdHFFelicaSimLite(const char *Cmd) {
     return PM3_SUCCESS;
 }
 
-static void printSep() {
+static void printSep(void) {
     PrintAndLogEx(INFO, "------------------------------------------------------------------------------------");
 }
 
diff --git a/client/src/cmdhficlass.c b/client/src/cmdhficlass.c
index d05afdae2..e46f045a3 100644
--- a/client/src/cmdhficlass.c
+++ b/client/src/cmdhficlass.c
@@ -191,7 +191,7 @@ static int usage_hf_iclass_readblock(void) {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_hf_iclass_readtagfile() {
+static int usage_hf_iclass_readtagfile(void) {
     PrintAndLogEx(NORMAL, "Print a iClass tag-dump file\n");
     PrintAndLogEx(NORMAL, "Usage: hf iClass readtagfile [f <filename>] [s <startblock>] [e <endblock>] [v]\n");
     PrintAndLogEx(NORMAL, "Options:");
diff --git a/client/src/cmdhflist.c b/client/src/cmdhflist.c
index 7aeac0bc7..16fdb309e 100644
--- a/client/src/cmdhflist.c
+++ b/client/src/cmdhflist.c
@@ -37,7 +37,7 @@ enum MifareAuthSeq {
 static enum MifareAuthSeq MifareAuthState;
 static TAuthData AuthData;
 
-void ClearAuthData() {
+void ClearAuthData(void) {
     AuthData.uid = 0;
     AuthData.nt = 0;
     AuthData.first_auth = true;
diff --git a/client/src/cmdhfmf.c b/client/src/cmdhfmf.c
index 95e821781..ba017676c 100644
--- a/client/src/cmdhfmf.c
+++ b/client/src/cmdhfmf.c
@@ -3132,7 +3132,7 @@ out:
 sector_t *k_sector = NULL;
 uint8_t k_sectorsCount = 40;
 
-void showSectorTable() {
+void showSectorTable(void) {
     if (k_sector != NULL) {
         printKeyTable(k_sectorsCount, k_sector);
         free(k_sector);
@@ -4806,7 +4806,7 @@ static int CmdHFMFNDEF(const char *Cmd) {
     return PM3_SUCCESS;
 }
 
-int CmdHFMFPersonalize(const char *cmd) {
+static int CmdHFMFPersonalize(const char *cmd) {
 
     CLIParserInit("hf mf personalize",
                   "Personalize the UID of a Mifare Classic EV1 card. This is only possible if it is a 7Byte UID card and if it is not already personalized.",
diff --git a/client/src/cmdhfmfhard.c b/client/src/cmdhfmfhard.c
index 6fc146164..b8f3c0471 100644
--- a/client/src/cmdhfmfhard.c
+++ b/client/src/cmdhfmfhard.c
@@ -1302,7 +1302,7 @@ static void simulate_MFplus_RNG(uint32_t test_cuid, uint64_t test_key, uint32_t
 
 }
 
-static void simulate_acquire_nonces() {
+static void simulate_acquire_nonces(void) {
     time_t time1 = time(NULL);
     last_sample_clock = 0;
     sample_period = 1000; // for simulation
@@ -2108,7 +2108,7 @@ static uint16_t SumProperty(struct Crypto1State *s) {
     return (sum_odd * (16 - sum_even) + (16 - sum_odd) * sum_even);
 }
 
-static void Tests() {
+static void Tests(void) {
 
     if (known_target_key == -1)
         return;
diff --git a/client/src/cmdhfmfp.c b/client/src/cmdhfmfp.c
index 728101ce7..f9d2e661a 100644
--- a/client/src/cmdhfmfp.c
+++ b/client/src/cmdhfmfp.c
@@ -949,7 +949,7 @@ static int CmdHFMFPWrbl(const char *Cmd) {
 #define AES_KEY_LEN        16
 #define MAX_KEYS_LIST_LEN  1024
 
-int MFPKeyCheck(uint8_t startSector, uint8_t endSector, uint8_t startKeyAB, uint8_t endKeyAB,
+static int MFPKeyCheck(uint8_t startSector, uint8_t endSector, uint8_t startKeyAB, uint8_t endKeyAB,
                 uint8_t keyList[MAX_KEYS_LIST_LEN][AES_KEY_LEN], size_t keyListLen, uint8_t foundKeys[2][64][AES_KEY_LEN + 1],
                 bool verbose) {
     int res;
@@ -1027,7 +1027,7 @@ int MFPKeyCheck(uint8_t startSector, uint8_t endSector, uint8_t startKeyAB, uint
     return PM3_SUCCESS;
 }
 
-void Fill2bPattern(uint8_t keyList[MAX_KEYS_LIST_LEN][AES_KEY_LEN], size_t *keyListLen, uint32_t *startPattern) {
+static void Fill2bPattern(uint8_t keyList[MAX_KEYS_LIST_LEN][AES_KEY_LEN], size_t *keyListLen, uint32_t *startPattern) {
     for (uint32_t pt = *startPattern; pt < 0x10000; pt++) {
         keyList[*keyListLen][0] = (pt >> 8) & 0xff;
         keyList[*keyListLen][1] = pt & 0xff;
diff --git a/client/src/cmdhfmfu.c b/client/src/cmdhfmfu.c
index 88e44285e..c71cff645 100644
--- a/client/src/cmdhfmfu.c
+++ b/client/src/cmdhfmfu.c
@@ -855,7 +855,7 @@ static int ulev1_print_configuration(uint32_t tagtype, uint8_t *data, uint8_t st
     return PM3_SUCCESS;
 }
 
-static int ulev1_print_counters() {
+static int ulev1_print_counters(void) {
     PrintAndLogEx(INFO, "--- " _CYAN_("Tag Counters"));
     uint8_t tear[1] = {0};
     uint8_t counter[3] = {0, 0, 0};
@@ -1004,7 +1004,7 @@ static int ulc_magic_test(){
     return returnValue;
 }
 */
-static int ul_magic_test() {
+static int ul_magic_test(void) {
     // Magic Ultralight tests
     // 1) take present UID, and try to write it back. OBSOLETE
     // 2) make a wrong length write to page0, and see if tag answers with ACK/NACK:
diff --git a/client/src/cmdlf.c b/client/src/cmdlf.c
index a08ec2b9e..520407847 100644
--- a/client/src/cmdlf.c
+++ b/client/src/cmdlf.c
@@ -670,7 +670,7 @@ int CmdLFSniff(const char *Cmd) {
     return PM3_SUCCESS;
 }
 
-static void ChkBitstream() {
+static void ChkBitstream(void) {
     // convert to bitstream if necessary
     for (int i = 0; i < (int)(GraphTraceLen / 2); i++) {
         if (GraphBuffer[i] > 1 || GraphBuffer[i] < 0) {
diff --git a/client/src/cmdlfem4x.c b/client/src/cmdlfem4x.c
index f0e51b900..f3986b19d 100644
--- a/client/src/cmdlfem4x.c
+++ b/client/src/cmdlfem4x.c
@@ -1055,7 +1055,7 @@ static int CmdEM4x50Dump(const char *Cmd) {
 
 #define EM_PREAMBLE_LEN 6
 // download samples from device and copy to Graphbuffer
-static bool downloadSamplesEM() {
+static bool downloadSamplesEM(void) {
 
     // 8 bit preamble + 32 bit word response (max clock (128) * 40bits = 5120 samples)
     uint8_t got[6000];
@@ -1097,7 +1097,7 @@ static bool doPreambleSearch(size_t *startIdx) {
     return true;
 }
 
-static bool detectFSK() {
+static bool detectFSK(void) {
     // detect fsk clock
     if (GetFskClock("", false) == 0) {
         PrintAndLogEx(DEBUG, "DEBUG: Error - EM: FSK clock failed");
@@ -1112,7 +1112,7 @@ static bool detectFSK() {
     return true;
 }
 // PSK clocks should be easy to detect ( but difficult to demod a non-repeating pattern... )
-static bool detectPSK() {
+static bool detectPSK(void) {
     int ans = GetPskClock("", false);
     if (ans <= 0) {
         PrintAndLogEx(DEBUG, "DEBUG: Error - EM: PSK clock failed");
@@ -1136,7 +1136,7 @@ static bool detectPSK() {
     return true;
 }
 // try manchester - NOTE: ST only applies to T55x7 tags.
-static bool detectASK_MAN() {
+static bool detectASK_MAN(void) {
     bool stcheck = false;
     if (ASKDemod_ext("0 0 0", false, false, 1, &stcheck) != PM3_SUCCESS) {
         PrintAndLogEx(DEBUG, "DEBUG: Error - EM: ASK/Manchester Demod failed");
@@ -1145,7 +1145,7 @@ static bool detectASK_MAN() {
     return true;
 }
 
-static bool detectASK_BI() {
+static bool detectASK_BI(void) {
     int ans = ASKbiphaseDemod("0 0 1", false);
     if (ans != PM3_SUCCESS) {
         PrintAndLogEx(DEBUG, "DEBUG: Error - EM: ASK/biphase normal demod failed");
@@ -1158,7 +1158,7 @@ static bool detectASK_BI() {
     }
     return true;
 }
-static bool detectNRZ() {
+static bool detectNRZ(void) {
     int ans = NRZrawDemod("0 0 1", false);
     if (ans != PM3_SUCCESS) {
         PrintAndLogEx(DEBUG, "DEBUG: Error - EM: NRZ normal demod failed");
diff --git a/client/src/cmdlfhitag.c b/client/src/cmdlfhitag.c
index 47971c713..4c35fedf1 100644
--- a/client/src/cmdlfhitag.c
+++ b/client/src/cmdlfhitag.c
@@ -22,7 +22,7 @@
 
 static int CmdHelp(const char *Cmd);
 
-static char *getHitagTypeStr(uint32_t uid) {
+static const char *getHitagTypeStr(uint32_t uid) {
     //uid s/n        ********
     uint8_t type = (uid >> 4) & 0xF;
     switch (type) {
diff --git a/client/src/cmdlfpcf7931.c b/client/src/cmdlfpcf7931.c
index 4c2c9848c..2062c8582 100644
--- a/client/src/cmdlfpcf7931.c
+++ b/client/src/cmdlfpcf7931.c
@@ -32,7 +32,7 @@ struct pcf7931_config configPcf = {
 };
 
 // Resets the configuration settings to default values.
-int pcf7931_resetConfig() {
+int pcf7931_resetConfig(void) {
     memset(configPcf.Pwd, 0xFF, sizeof(configPcf.Pwd));
     configPcf.InitDelay = PCF7931_DEFAULT_INITDELAY;
     configPcf.OffsetWidth = PCF7931_DEFAULT_OFFSET_WIDTH;
@@ -40,7 +40,7 @@ int pcf7931_resetConfig() {
     return PM3_SUCCESS;
 }
 
-int pcf7931_printConfig() {
+int pcf7931_printConfig(void) {
     PrintAndLogEx(NORMAL, "Password (LSB first on bytes) : %s", sprint_hex(configPcf.Pwd, sizeof(configPcf.Pwd)));
     PrintAndLogEx(NORMAL, "Tag initialization delay      : %d us", configPcf.InitDelay);
     PrintAndLogEx(NORMAL, "Offset low pulses width       : %d us", configPcf.OffsetWidth);
@@ -48,7 +48,7 @@ int pcf7931_printConfig() {
     return PM3_SUCCESS;
 }
 
-static int usage_pcf7931_read() {
+static int usage_pcf7931_read(void) {
     PrintAndLogEx(NORMAL, "Usage: lf pcf7931 read [h] ");
     PrintAndLogEx(NORMAL, "This command tries to read a PCF7931 tag.");
     PrintAndLogEx(NORMAL, "Options:");
@@ -58,7 +58,7 @@ static int usage_pcf7931_read() {
     return PM3_SUCCESS;
 }
 
-static int usage_pcf7931_write() {
+static int usage_pcf7931_write(void) {
     PrintAndLogEx(NORMAL, "Usage: lf pcf7931 write [h] <block address> <byte address> <data>");
     PrintAndLogEx(NORMAL, "This command tries to write a PCF7931 tag.");
     PrintAndLogEx(NORMAL, "Options:");
@@ -71,7 +71,7 @@ static int usage_pcf7931_write() {
     return PM3_SUCCESS;
 }
 
-static int usage_pcf7931_config() {
+static int usage_pcf7931_config(void) {
     PrintAndLogEx(NORMAL, "Usage: lf pcf7931 config [h] [r] <pwd> <delay> <offset width> <offset position>");
     PrintAndLogEx(NORMAL, "This command tries to set the configuration used with PCF7931 commands");
     PrintAndLogEx(NORMAL, "The time offsets could be useful to correct slew rate generated by the antenna");
diff --git a/client/src/cmdlft55xx.c b/client/src/cmdlft55xx.c
index 09f2009bd..7f7eccb19 100644
--- a/client/src/cmdlft55xx.c
+++ b/client/src/cmdlft55xx.c
@@ -57,7 +57,7 @@ t55xx_conf_block_t config = {
 
 t55xx_memory_item_t cardmem[T55x7_BLOCK_COUNT] = {{0}};
 
-t55xx_conf_block_t Get_t55xx_Config() {
+t55xx_conf_block_t Get_t55xx_Config(void) {
     return config;
 }
 
@@ -78,7 +78,7 @@ static void print_usage_t55xx_downloadlink(uint8_t ShowAll, uint8_t dl_mode_defa
         PrintAndLogEx(NORMAL, "                       4 - Try all downlink modes%s", (dl_mode_default == 4) ? " (default)" : "");
 }
 
-static int usage_t55xx_config() {
+static int usage_t55xx_config(void) {
     PrintAndLogEx(NORMAL, "Usage: lf t55xx config [c <blk0>] [d <demodulation>] [i [0/1]] [o <offset>] [Q5 [0/1]] [ST [0/1]]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     h                                - This help");
@@ -99,7 +99,7 @@ static int usage_t55xx_config() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_read() {
+static int usage_t55xx_read(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx read [r <mode>] b <block> [p <password>] [o] <page1>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     b <block>    - block number to read. Between 0-7");
@@ -119,7 +119,7 @@ static int usage_t55xx_read() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_resetread() {
+static int usage_t55xx_resetread(void) {
     PrintAndLogEx(NORMAL, "Send Reset Cmd then lf read the stream to attempt to identify the start of it (needs a demod and/or plot after)");
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx resetread [r <mode>]");
     PrintAndLogEx(NORMAL, "Options:");
@@ -130,7 +130,7 @@ static int usage_t55xx_resetread() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_write() {
+static int usage_t55xx_write(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx write [r <mode>] b <block> d <data> [p <password>] [1] [t] [v]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     b <block>    - block number to write. Between 0-7");
@@ -148,7 +148,7 @@ static int usage_t55xx_write() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_trace() {
+static int usage_t55xx_trace(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx trace [1] [r mode]");
     PrintAndLogEx(NORMAL, "Options:");
     print_usage_t55xx_downloadlink(T55XX_DLMODE_SINGLE, config.downlink_mode);
@@ -160,7 +160,7 @@ static int usage_t55xx_trace() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_info() {
+static int usage_t55xx_info(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx info [1] [r <mode>] [c <blk0> [q]]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     (default)    - read data from tag.");
@@ -180,7 +180,7 @@ static int usage_t55xx_info() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_dump() {
+static int usage_t55xx_dump(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx dump [r <mode>] [p <password> [o]]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     p <password> - OPTIONAL password 4bytes (8 hex symbols)");
@@ -194,7 +194,7 @@ static int usage_t55xx_dump() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_restore() {
+static int usage_t55xx_restore(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx restore f <filename> [p password]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     f <filename> - filename of the dump file (.bin/.eml)");
@@ -208,7 +208,7 @@ static int usage_t55xx_restore() {
     return PM3_SUCCESS;
 }
 
-static int usage_t55xx_detect() {
+static int usage_t55xx_detect(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx detect [1] [r <mode>] [p <password>]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     1            - if set, use Graphbuffer otherwise read data from tag.");
@@ -222,7 +222,7 @@ static int usage_t55xx_detect() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_detectP1() {
+static int usage_t55xx_detectP1(void) {
     PrintAndLogEx(NORMAL, "Command: Detect Page 1 of a t55xx chip");
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx p1detect [1] [r <mode>] [p <password>]");
     PrintAndLogEx(NORMAL, "Options:");
@@ -237,7 +237,7 @@ static int usage_t55xx_detectP1() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_wakup() {
+static int usage_t55xx_wakup(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx wakeup [h] [r <mode>] p <password>");
     PrintAndLogEx(NORMAL, "This commands sends the Answer-On-Request command and leaves the readerfield ON afterwards.");
     PrintAndLogEx(NORMAL, "Options:");
@@ -249,7 +249,7 @@ static int usage_t55xx_wakup() {
     PrintAndLogEx(NORMAL, "      lf t55xx wakeup p 11223344  - send wakeup password");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_chk() {
+static int usage_t55xx_chk(void) {
     PrintAndLogEx(NORMAL, "This command uses a dictionary attack");
     PrintAndLogEx(NORMAL, "press " _YELLOW_("'enter'") " to cancel the command");
     PrintAndLogEx(NORMAL,  _RED_("WARNING:") " this may brick non-password protected chips!");
@@ -267,7 +267,7 @@ static int usage_t55xx_chk() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_bruteforce() {
+static int usage_t55xx_bruteforce(void) {
     PrintAndLogEx(NORMAL, "This command uses bruteforce to scan a number range");
     PrintAndLogEx(NORMAL, "press " _YELLOW_("'enter'") " to cancel the command");
     PrintAndLogEx(NORMAL, _RED_("WARNING:") " this may brick non-password protected chips!");
@@ -285,7 +285,7 @@ static int usage_t55xx_bruteforce() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_recoverpw() {
+static int usage_t55xx_recoverpw(void) {
     PrintAndLogEx(NORMAL, "This command uses a few tricks to try to recover mangled password");
     PrintAndLogEx(NORMAL, "press " _YELLOW_("'enter'") " to cancel the command");
     PrintAndLogEx(NORMAL, _RED_("WARNING:") " this may brick non-password protected chips!");
@@ -306,7 +306,7 @@ static int usage_t55xx_recoverpw() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_wipe() {
+static int usage_t55xx_wipe(void) {
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx wipe [h] [Q5] [p <password>] [c <blk0>]");
     PrintAndLogEx(NORMAL, "This commands wipes a tag, fills blocks 1-7 with zeros and a default configuration block");
     PrintAndLogEx(NORMAL, "Options:");
@@ -319,7 +319,7 @@ static int usage_t55xx_wipe() {
     PrintAndLogEx(NORMAL, "      lf t55xx wipe q    -  wipes a T5555 ( Q5 ) tag, config block 0x6001F004");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_deviceconfig() {
+static int usage_t55xx_deviceconfig(void) {
     PrintAndLogEx(NORMAL, "Sets t55x7 timings for direct commands. The timings are set here in Field Clocks (FC), \nwhich is converted to (US) on device");
     PrintAndLogEx(NORMAL, "Usage: lf t55xx deviceconfig [r <mode>] a <gap> b <gap> c <gap> d <gap> e <gap> f <gap> g <gap> [p]");
     PrintAndLogEx(NORMAL, "Options:");
@@ -340,7 +340,7 @@ static int usage_t55xx_deviceconfig() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_protect() {
+static int usage_t55xx_protect(void) {
     PrintAndLogEx(NORMAL, "This command sets the pwd bit on T5577.");
     PrintAndLogEx(NORMAL, _RED_("WARNING:") " this locks the tag!");
     PrintAndLogEx(NORMAL, "Usage:  lf t55xx protect [r <mode>] [p <password>] [o] [n <new_password>]");
@@ -356,7 +356,7 @@ static int usage_t55xx_protect() {
     PrintAndLogEx(NORMAL, "");
     return PM3_SUCCESS;
 }
-static int usage_t55xx_dangerraw() {
+static int usage_t55xx_dangerraw(void) {
     PrintAndLogEx(NORMAL, "This command allows to emit arbitrary raw commands on T5577 and cut the field after arbitrary duration.");
     PrintAndLogEx(NORMAL, _RED_("WARNING:") " this may lock definitively the tag in an unusable state!");
     PrintAndLogEx(NORMAL, "Uncontrolled usage can easily write an invalid configuration, activate lock bits,");
@@ -372,7 +372,7 @@ static int usage_t55xx_dangerraw() {
     return PM3_SUCCESS;
 }
 
-static int usage_t55xx_clonehelp() {
+static int usage_t55xx_clonehelp(void) {
     PrintAndLogEx(NORMAL, "For cloning specific techs on T55xx tags, see commands available in corresponding LF sub-menus, e.g.:");
     PrintAndLogEx(NORMAL, _GREEN_("lf awid clone"));
 // todo:  rename to clone
@@ -408,13 +408,13 @@ static int CmdT55xxCloneHelp(const char *Cmd) {
     return usage_t55xx_clonehelp();
 }
 
-void T55x7_SaveBlockData(uint8_t idx, uint32_t data) {
+static void T55x7_SaveBlockData(uint8_t idx, uint32_t data) {
     if (idx < T55x7_BLOCK_COUNT) {
         cardmem[idx].valid      = true;
         cardmem[idx].blockdata  = data;
     }
 }
-void T55x7_ClearAllBlockData(void) {
+static void T55x7_ClearAllBlockData(void) {
     for (uint8_t idx = 0; idx < T55x7_BLOCK_COUNT; idx++) {
         cardmem[idx].valid      = false;
         cardmem[idx].blockdata  = 0x00;
@@ -1011,7 +1011,7 @@ static int SanityOfflineCheck(bool useGraphBuffer) {
     return PM3_SUCCESS;
 }
 
-void T55xx_Print_DownlinkMode(uint8_t downlink_mode) {
+static void T55xx_Print_DownlinkMode(uint8_t downlink_mode) {
     char msg[80];
     sprintf(msg, "Downlink Mode used : ");
 
diff --git a/client/src/cmdmain.c b/client/src/cmdmain.c
index f9cfe310a..1e9c8d257 100644
--- a/client/src/cmdmain.c
+++ b/client/src/cmdmain.c
@@ -79,7 +79,7 @@ static int usage_auto(void) {
     return PM3_SUCCESS;
 }
 
-static void AppendDate(char *s, size_t slen, char *fmt) {
+static void AppendDate(char *s, size_t slen, const char *fmt) {
     struct tm *ct, tm_buf;
     time_t now = time(NULL);
 #if defined(_WIN32)
@@ -287,7 +287,7 @@ int CommandReceived(char *Cmd) {
     return CmdsParse(CommandTable, Cmd);
 }
 
-command_t *getTopLevelCommandTable() {
+command_t *getTopLevelCommandTable(void) {
     return CommandTable;
 }
 
diff --git a/client/src/cmdsmartcard.c b/client/src/cmdsmartcard.c
index ba48fae96..f21ef5c4a 100644
--- a/client/src/cmdsmartcard.c
+++ b/client/src/cmdsmartcard.c
@@ -875,7 +875,7 @@ static int CmdSmartList(const char *Cmd) {
     return 0;
 }
 
-static void smart_brute_prim() {
+static void smart_brute_prim(void) {
 
     uint8_t *buf = calloc(PM3_CMD_DATA_SIZE, sizeof(uint8_t));
     if (!buf)
diff --git a/client/src/cmdtrace.c b/client/src/cmdtrace.c
index 41c102aa1..85d2bea09 100644
--- a/client/src/cmdtrace.c
+++ b/client/src/cmdtrace.c
@@ -25,7 +25,7 @@ static int CmdHelp(const char *Cmd);
 static uint8_t *trace;
 long traceLen = 0;
 
-static int usage_trace_list() {
+static int usage_trace_list(void) {
     PrintAndLogEx(NORMAL, "List protocol data in trace buffer.");
     PrintAndLogEx(NORMAL, "Usage:  trace list <protocol> [f][c| <0|1>");
     PrintAndLogEx(NORMAL, "    f      - show frame delay times as well");
@@ -56,14 +56,14 @@ static int usage_trace_list() {
     PrintAndLogEx(NORMAL, "        trace list iclass");
     return PM3_SUCCESS;
 }
-static int usage_trace_load() {
+static int usage_trace_load(void) {
     PrintAndLogEx(NORMAL, "Load protocol data from file to trace buffer.");
     PrintAndLogEx(NORMAL, "Usage:  trace load <filename>");
     PrintAndLogEx(NORMAL, "Examples:");
     PrintAndLogEx(NORMAL, "        trace load mytracefile.bin");
     return PM3_SUCCESS;
 }
-static int usage_trace_save() {
+static int usage_trace_save(void) {
     PrintAndLogEx(NORMAL, "Save protocol data from trace buffer to file.");
     PrintAndLogEx(NORMAL, "Usage:  trace save <filename>");
     PrintAndLogEx(NORMAL, "Examples:");
diff --git a/client/src/cmdusart.c b/client/src/cmdusart.c
index 3168d66b7..56d4b88bb 100644
--- a/client/src/cmdusart.c
+++ b/client/src/cmdusart.c
@@ -274,7 +274,7 @@ static int usart_bt_testcomm(uint32_t baudrate, uint8_t parity) {
     if (ret != PM3_SUCCESS)
         return ret;
 
-    char *string = "AT+VERSION";
+    const char *string = "AT+VERSION";
     uint8_t data[PM3_CMD_DATA_SIZE] = {0x00};
     size_t len = 0;
 
@@ -359,7 +359,7 @@ static int CmdUsartBtFactory(const char *Cmd) {
     }
 
     PrintAndLogEx(INFO, "Reconfiguring add-on to default settings.");
-    char *string;
+    const char *string;
     uint8_t data[PM3_CMD_DATA_SIZE];
     size_t len = 0;
     memset(data, 0, sizeof(data));
diff --git a/client/src/cmdwiegand.c b/client/src/cmdwiegand.c
index 3c939261f..19f166284 100644
--- a/client/src/cmdwiegand.c
+++ b/client/src/cmdwiegand.c
@@ -24,11 +24,11 @@
 
 static int CmdHelp(const char *Cmd);
 
-static int usage_wiegand_list() {
+static int usage_wiegand_list(void) {
     PrintAndLogEx(NORMAL, "List available wiegand formats");
     return PM3_SUCCESS;
 }
-static int usage_wiegand_encode() {
+static int usage_wiegand_encode(void) {
     PrintAndLogEx(NORMAL, "Encode wiegand formatted number to raw hex");
     PrintAndLogEx(NORMAL, "Usage:  wiegand encode [w <format>] [<field> <value (decimal)>] {...}");
     PrintAndLogEx(NORMAL, "Options:");
@@ -42,7 +42,7 @@ static int usage_wiegand_encode() {
     PrintAndLogEx(NORMAL, "      wiegand encode w H10301 f 101 c 1337");
     return PM3_SUCCESS;
 }
-static int usage_wiegand_decode() {
+static int usage_wiegand_decode(void) {
     PrintAndLogEx(NORMAL, "Decode raw hex to wiegand format");
     PrintAndLogEx(NORMAL, "Usage:  wiegand decode [id] <p>");
     PrintAndLogEx(NORMAL, "        p         ignore invalid parity");
@@ -52,7 +52,7 @@ static int usage_wiegand_decode() {
     return PM3_SUCCESS;
 }
 
-void PrintTagId(wiegand_message_t *packed) {
+static void PrintTagId(wiegand_message_t *packed) {
     if (packed->Top != 0) {
         PrintAndLogEx(SUCCESS, "Card ID: %X%08X%08X",
                       (uint32_t)packed->Top,
diff --git a/client/src/comms.c b/client/src/comms.c
index 36f035bdd..de5eafb24 100644
--- a/client/src/comms.c
+++ b/client/src/comms.c
@@ -202,7 +202,7 @@ void SendCommandMIX(uint64_t cmd, uint64_t arg0, uint64_t arg1, uint64_t arg2, v
  *  A better method could have been to have explicit command-ACKS, so we can know which ACK goes to which
  *  operation. Right now we'll just have to live with this.
  */
-void clearCommandBuffer() {
+void clearCommandBuffer(void) {
     //This is a very simple operation
     pthread_mutex_lock(&rxBufferMutex);
     cmd_tail = cmd_head;
diff --git a/client/src/fileutils.c b/client/src/fileutils.c
index 4ccd4fa8f..ac9196e4c 100644
--- a/client/src/fileutils.c
+++ b/client/src/fileutils.c
@@ -1360,7 +1360,7 @@ static int searchFinalFile(char **foundpath, const char *pm3dir, const char *sea
              (strcmp(FIRMWARES_SUBDIR, pm3dir) == 0) ||
              (strcmp(BOOTROM_SUBDIR, pm3dir) == 0) ||
              (strcmp(FULLIMAGE_SUBDIR, pm3dir) == 0))) {
-        char *above = "../";
+        const char *above = "../";
         char *path = calloc(strlen(exec_path) + strlen(above) + strlen(pm3dir) + strlen(filename) + 1, sizeof(char));
         if (path == NULL)
             goto out;
diff --git a/client/src/graph.c b/client/src/graph.c
index d5f62a6b7..2d75f3d30 100644
--- a/client/src/graph.c
+++ b/client/src/graph.c
@@ -116,7 +116,7 @@ bool isGraphBitstream(void) {
     return true;
 }
 
-void convertGraphFromBitstream() {
+void convertGraphFromBitstream(void) {
     convertGraphFromBitstreamEx(1, 0);
 }
 
diff --git a/client/src/loclass/cipher.c b/client/src/loclass/cipher.c
index 080ff66f5..9cc683300 100644
--- a/client/src/loclass/cipher.c
+++ b/client/src/loclass/cipher.c
@@ -283,7 +283,7 @@ void doMAC_N(uint8_t *address_data_p, uint8_t address_data_size, uint8_t *div_ke
 }
 
 #ifndef ON_DEVICE
-int testMAC() {
+int testMAC(void) {
     PrintAndLogEx(SUCCESS, "Testing MAC calculation...");
 
     //From the "dismantling.IClass" paper:
diff --git a/client/src/loclass/cipherutils.c b/client/src/loclass/cipherutils.c
index 09f4bccd7..95628226d 100644
--- a/client/src/loclass/cipherutils.c
+++ b/client/src/loclass/cipherutils.c
@@ -190,7 +190,7 @@ void printarr_human_readable(const char *title, uint8_t *arr, int len) {
 //-----------------------------
 
 #ifndef ON_DEVICE
-static int testBitStream() {
+static int testBitStream(void) {
     uint8_t input [] = {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
     uint8_t output [] = {0, 0, 0, 0, 0, 0, 0, 0};
     BitstreamIn in = { input, sizeof(input) * 8, 0};
@@ -215,7 +215,7 @@ static int testBitStream() {
     return PM3_SUCCESS;
 }
 
-static int testReversedBitstream() {
+static int testReversedBitstream(void) {
     uint8_t input [] = {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
     uint8_t reverse [] = {0, 0, 0, 0, 0, 0, 0, 0};
     uint8_t output [] = {0, 0, 0, 0, 0, 0, 0, 0};
diff --git a/client/src/loclass/elite_crack.c b/client/src/loclass/elite_crack.c
index 03a9a3080..5ef58f01e 100644
--- a/client/src/loclass/elite_crack.c
+++ b/client/src/loclass/elite_crack.c
@@ -568,7 +568,7 @@ int bruteforceFileNoKeys(const char *filename) {
 // ----------------------------------------------------------------------------
 // TEST CODE BELOW
 // ----------------------------------------------------------------------------
-static int _testBruteforce() {
+static int _testBruteforce(void) {
 
     PrintAndLogEx(INFO, "Testing crack from dumpfile...");
 
@@ -596,7 +596,7 @@ static int _testBruteforce() {
     return errors;
 }
 
-static int _test_iclass_key_permutation() {
+static int _test_iclass_key_permutation(void) {
     uint8_t testcase[8] = {0x6c, 0x8d, 0x44, 0xf9, 0x2a, 0x2d, 0x01, 0xbf};
     uint8_t testcase_output[8] = {0};
     uint8_t testcase_output_correct[8] = {0x8a, 0x0d, 0xb9, 0x88, 0xbb, 0xa7, 0x90, 0xea};
@@ -622,7 +622,7 @@ static int _test_iclass_key_permutation() {
     return 0;
 }
 
-static int _testHash1() {
+static int _testHash1(void) {
     uint8_t expected[8] = {0x7E, 0x72, 0x2F, 0x40, 0x2D, 0x02, 0x51, 0x42};
     uint8_t csn[8] = {0x01, 0x02, 0x03, 0x04, 0xF7, 0xFF, 0x12, 0xE0};
     uint8_t k[8] = {0};
diff --git a/client/src/loclass/ikeys.c b/client/src/loclass/ikeys.c
index 11a082867..3bbe9fc2b 100644
--- a/client/src/loclass/ikeys.c
+++ b/client/src/loclass/ikeys.c
@@ -219,7 +219,7 @@ static void permute(BitstreamIn *p_in, uint64_t z, int l, int r, BitstreamOut *o
     }
 }
 
-static void printbegin() {
+static void printbegin(void) {
     if (debug_print < 2)
         return;
 
@@ -369,7 +369,7 @@ void diversifyKey(uint8_t csn[8], uint8_t key[8], uint8_t div_key[8]) {
     hash0(crypt_csn, div_key);
 }
 /*
-static void testPermute() {
+static void testPermute(void) {
     uint64_t x = 0;
     pushbackSixBitByte(&x, 0x00, 0);
     pushbackSixBitByte(&x, 0x01, 1);
@@ -555,7 +555,7 @@ Testcase testcases[] = {
     {{0}, {0}, {0}}
 };
 
-static int testKeyDiversificationWithMasterkeyTestcases() {
+static int testKeyDiversificationWithMasterkeyTestcases(void) {
     int i, error = 0;
     uint8_t empty[8] = {0};
 
@@ -630,7 +630,7 @@ static int testDES2(uint64_t csn, uint64_t expected) {
  * @brief doTestsWithKnownInputs
  * @return
  */
-static int doTestsWithKnownInputs() {
+static int doTestsWithKnownInputs(void) {
     // KSel from http://www.proxmark.org/forum/viewtopic.php?pid=10977#p10977
     int errors = 0;
     PrintAndLogEx(SUCCESS, "Testing DES encryption");
diff --git a/client/src/pm3_binlib.c b/client/src/pm3_binlib.c
index d694ee3b0..f4e49c137 100644
--- a/client/src/pm3_binlib.c
+++ b/client/src/pm3_binlib.c
@@ -318,6 +318,7 @@ static const luaL_Reg binlib[] = {
     {NULL,     NULL}
 };
 
+LUALIB_API int luaopen_binlib(lua_State *L);
 LUALIB_API int luaopen_binlib(lua_State *L) {
     luaL_newlib(L, binlib);
     return 1;
diff --git a/client/src/pm3_bitlib.c b/client/src/pm3_bitlib.c
index 15fdbd5d0..b5ef6e0ae 100644
--- a/client/src/pm3_bitlib.c
+++ b/client/src/pm3_bitlib.c
@@ -126,6 +126,7 @@ static const struct luaL_Reg bitlib[] = {
     {NULL, NULL}
 };
 
+LUALIB_API int luaopen_bit(lua_State *L);
 LUALIB_API int luaopen_bit(lua_State *L) {
     luaL_newlib(L, bitlib);
     //luaL_register(L, "bit", bitlib);
diff --git a/client/src/preferences.c b/client/src/preferences.c
index 4f92eb06e..0ef715075 100644
--- a/client/src/preferences.c
+++ b/client/src/preferences.c
@@ -44,7 +44,7 @@ static char *prefGetFilename(void) {
     if (searchHomeFilePath(&path, preferencesFilename, false) == PM3_SUCCESS)
         return path;
     else
-        return preferencesFilename;
+        return strdup(preferencesFilename);
 }
 
 int preferences_load(void) {
@@ -314,7 +314,7 @@ void preferences_load_callback(json_t *root) {
 
 // Help Functions
 
-static int usage_set_emoji() {
+static int usage_set_emoji(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set emoji <alias | emoji | alttext | erase>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -325,7 +325,7 @@ static int usage_set_emoji() {
     return PM3_SUCCESS;
 }
 
-static int usage_set_color() {
+static int usage_set_color(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set color <off | ansi>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -334,7 +334,7 @@ static int usage_set_color() {
     return PM3_SUCCESS;
 }
 
-static int usage_set_debug() {
+static int usage_set_debug(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set clientdebug <off | simple | full>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -344,7 +344,7 @@ static int usage_set_debug() {
     return PM3_SUCCESS;
 }
 /*
-static int usage_set_devicedebug() {
+static int usage_set_devicedebug(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set devicedebug <off | error | info | debug | extended>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -357,7 +357,7 @@ static int usage_set_devicedebug() {
     return PM3_SUCCESS;
 }
 */
-static int usage_set_hints() {
+static int usage_set_hints(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set hints <off | on>");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -366,7 +366,7 @@ static int usage_set_hints() {
     return PM3_SUCCESS;
 }
 /*
-static int usage_set_savePaths() {
+static int usage_set_savePaths(void) {
     PrintAndLogEx(NORMAL, "Usage: pref set savepaths [help] [create] [default <path>] [dump <path>] [trace <path>]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "     "_GREEN_("help")"        - This help");
@@ -382,7 +382,7 @@ static int usage_set_savePaths() {
 // typedef enum preferenceId {prefNONE,prefHELP,prefEMOJI,prefCOLOR,prefPLOT,prefOVERLAY,prefHINTS,prefCLIENTDEBUG} preferenceId_t;
 typedef enum prefShowOpt {prefShowNone, prefShowOLD, prefShowNEW} prefShowOpt_t;
 
-const char *prefShowMsg(prefShowOpt_t Opt) {
+static const char *prefShowMsg(prefShowOpt_t Opt) {
     switch (Opt) {
         case prefShowOLD:
             return _YELLOW_("[old]");
@@ -395,7 +395,7 @@ const char *prefShowMsg(prefShowOpt_t Opt) {
     return "";
 }
 
-void showEmojiState(prefShowOpt_t Opt) {
+static void showEmojiState(prefShowOpt_t Opt) {
 
     switch (session.emoji_mode) {
         case ALIAS:
@@ -415,7 +415,7 @@ void showEmojiState(prefShowOpt_t Opt) {
     }
 }
 
-void showColorState(prefShowOpt_t Opt) {
+static void showColorState(prefShowOpt_t Opt) {
 
     if (session.supports_colors)
         PrintAndLogEx(NORMAL, "   %s color.................. "_GREEN_("ansi"), prefShowMsg(Opt));
@@ -423,7 +423,7 @@ void showColorState(prefShowOpt_t Opt) {
         PrintAndLogEx(NORMAL, "   %s color.................. "_WHITE_("off"), prefShowMsg(Opt));
 }
 
-void showClientDebugState(prefShowOpt_t Opt) {
+static void showClientDebugState(prefShowOpt_t Opt) {
 
     switch (session.client_debug_level) {
         case cdbOFF:
@@ -440,7 +440,7 @@ void showClientDebugState(prefShowOpt_t Opt) {
     }
 }
 /*
-void showDeviceDebugState(prefShowOpt_t Opt) {
+static void showDeviceDebugState(prefShowOpt_t Opt) {
     switch (session.device_debug_level) {
         case ddbOFF:
             PrintAndLogEx(NORMAL, "   %s device debug........... "_WHITE_("off"), prefShowMsg(Opt));
@@ -463,7 +463,7 @@ void showDeviceDebugState(prefShowOpt_t Opt) {
 }
 */
 /*
-void showSavePathState(savePaths_t pathIndex, prefShowOpt_t Opt) {
+static void showSavePathState(savePaths_t pathIndex, prefShowOpt_t Opt) {
 
     char tempStr[50];
 
@@ -485,18 +485,19 @@ void showSavePathState(savePaths_t pathIndex, prefShowOpt_t Opt) {
     else
         PrintAndLogEx(NORMAL, "   %s %s "_GREEN_("%s"), prefShowMsg(Opt), tempStr, session.defaultPaths[pathIndex]);
 }
-*/
-void showPlotPosState(void) {
+
+static void showPlotPosState(void) {
     PrintAndLogEx(NORMAL, "    Plot window............ X "_GREEN_("%4d")" Y "_GREEN_("%4d")" H "_GREEN_("%4d")" W "_GREEN_("%4d"),
                   session.plot.x, session.plot.y, session.plot.h, session.plot.w);
 }
 
-void showOverlayPosState(void) {
+static void showOverlayPosState(void) {
     PrintAndLogEx(NORMAL, "    Slider/Overlay window.. X "_GREEN_("%4d")" Y "_GREEN_("%4d")" H "_GREEN_("%4d")" W "_GREEN_("%4d"),
                   session.overlay.x, session.overlay.y, session.overlay.h, session.overlay.w);
 }
+*/
 
-void showHintsState(prefShowOpt_t Opt) {
+static void showHintsState(prefShowOpt_t Opt) {
     if (session.show_hints)
         PrintAndLogEx(NORMAL, "   %s hints.................. "_GREEN_("on"), prefShowMsg(Opt));
     else
@@ -850,28 +851,28 @@ static int setCmdSavePaths (const char *Cmd) {
 
     return PM3_SUCCESS;
 }
-*/
 
-int getCmdHelp(const char *Cmd) {
+static int getCmdHelp(const char *Cmd) {
     return PM3_SUCCESS;
 }
+*/
 
-int getCmdEmoji(const char *Cmd) {
+static int getCmdEmoji(const char *Cmd) {
     showEmojiState(prefShowNone);
     return PM3_SUCCESS;
 }
 
-int getCmdHint(const char *Cmd) {
+static int getCmdHint(const char *Cmd) {
     showHintsState(prefShowNone);
     return PM3_SUCCESS;
 }
 
-int getCmdColor(const char *Cmd) {
+static int getCmdColor(const char *Cmd) {
     showColorState(prefShowNone);
     return PM3_SUCCESS;
 }
 
-int getCmdDebug(const char *Cmd) {
+static int getCmdDebug(const char *Cmd) {
     showClientDebugState(prefShowNone);
     return PM3_SUCCESS;
 }
@@ -904,12 +905,12 @@ static int setCmdHelp(const char *Cmd) {
     return PM3_SUCCESS;
 }
 
-int CmdPrefGet(const char *Cmd) {
+static int CmdPrefGet(const char *Cmd) {
     clearCommandBuffer();
     return CmdsParse(getCommandTable, Cmd);
 }
 
-int CmdPrefSet(const char *Cmd) {
+static int CmdPrefSet(const char *Cmd) {
     clearCommandBuffer();
     return CmdsParse(setCommandTable, Cmd);
 }
diff --git a/client/src/proxgui.h b/client/src/proxgui.h
index c9cd0096d..bfcbc78e1 100644
--- a/client/src/proxgui.h
+++ b/client/src/proxgui.h
@@ -59,7 +59,6 @@ extern uint8_t g_debugMode;
 #ifndef FILE_PATH_SIZE
 #define FILE_PATH_SIZE 1000
 #endif
-extern uint8_t gui_serial_port_name[FILE_PATH_SIZE];
 
 #ifdef __cplusplus
 }
diff --git a/client/src/proxguiqt.cpp b/client/src/proxguiqt.cpp
index 855b41c87..59bbddb69 100644
--- a/client/src/proxguiqt.cpp
+++ b/client/src/proxguiqt.cpp
@@ -27,6 +27,7 @@
 #include "proxgui.h"
 #include <QtGui>
 #include "ui.h"
+#include "comms.h"
 
 extern "C" int preferences_save(void);
 
diff --git a/client/src/proxmark3.c b/client/src/proxmark3.c
index 6010fb981..80fd958b1 100644
--- a/client/src/proxmark3.c
+++ b/client/src/proxmark3.c
@@ -116,8 +116,8 @@ static void showBanner(void) {
 static const char *prompt_dev = "";
 static const char *prompt_ctx = "";
 
-static void prompt_compose(char *buf, size_t buflen, const char *prompt_ctx, const char *prompt_dev) {
-    snprintf(buf, buflen - 1, PROXPROMPT_COMPOSE, prompt_dev, prompt_ctx);
+static void prompt_compose(char *buf, size_t buflen, const char *promptctx, const char *promptdev) {
+    snprintf(buf, buflen - 1, PROXPROMPT_COMPOSE, promptdev, promptctx);
 }
 
 static int check_comm(void) {
@@ -155,11 +155,11 @@ int push_cmdscriptfile(char *path, bool stayafter) {
     return PM3_SUCCESS;
 }
 
-static FILE *current_cmdscriptfile() {
+static FILE *current_cmdscriptfile(void) {
     return cmdscriptfile[cmdscriptfile_idx];
 }
 
-static bool pop_cmdscriptfile() {
+static bool pop_cmdscriptfile(void) {
     fclose(cmdscriptfile[cmdscriptfile_idx]);
     cmdscriptfile[cmdscriptfile_idx--] = NULL;
     if (cmdscriptfile_idx == 0)
diff --git a/client/src/util.c b/client/src/util.c
index 3d0c6bd87..fb131e987 100644
--- a/client/src/util.c
+++ b/client/src/util.c
@@ -823,12 +823,6 @@ void wiegand_add_parity_swapped(uint8_t *target, uint8_t *source, uint8_t length
     *(target) = GetParity(source + length / 2, EVEN, length / 2);
 }
 
-// xor two arrays together for len items.  The dst array contains the new xored values.
-void xor(unsigned char *dst, unsigned char *src, size_t len) {
-    for (; len > 0; len--, dst++, src++)
-        *dst ^= *src;
-}
-
 // Pack a bitarray into a uint32_t.
 uint32_t PackBits(uint8_t start, uint8_t len, uint8_t *bits) {
 
diff --git a/client/src/util.h b/client/src/util.h
index 59591ac24..3f67c33f4 100644
--- a/client/src/util.h
+++ b/client/src/util.h
@@ -21,8 +21,8 @@
 # define FILE_PATH_SIZE 1000
 #endif
 
-uint8_t g_debugMode;
-uint8_t g_printAndLog;
+extern uint8_t g_debugMode;
+extern uint8_t g_printAndLog;
 
 #define PRINTANDLOG_PRINT 1
 #define PRINTANDLOG_LOG   2
diff --git a/client/src/wiegand_formats.c b/client/src/wiegand_formats.c
index 0c3c09fb6..13c08f143 100644
--- a/client/src/wiegand_formats.c
+++ b/client/src/wiegand_formats.c
@@ -602,7 +602,7 @@ static const cardformat_t FormatTable[] = {
     {NULL, NULL, NULL, NULL, {0, 0, 0, 0, 0}} // Must null terminate array
 };
 
-void HIDListFormats() {
+void HIDListFormats(void) {
     if (FormatTable[0].Name == NULL)
         return;
 
diff --git a/client/src/wiegand_formats.h b/client/src/wiegand_formats.h
index 2b9b3df05..4ac36fdcf 100644
--- a/client/src/wiegand_formats.h
+++ b/client/src/wiegand_formats.h
@@ -39,7 +39,7 @@ typedef struct {
     cardformatdescriptor_t Fields;
 } cardformat_t;
 
-void HIDListFormats();
+void HIDListFormats(void);
 int HIDFindCardFormat(const char *format);
 cardformat_t HIDGetCardFormat(int idx);
 bool HIDPack(int format_idx, wiegand_card_t *card, wiegand_message_t *packed);
diff --git a/client/src/wiegand_formatutils.c b/client/src/wiegand_formatutils.c
index 836da717d..cee0590ac 100644
--- a/client/src/wiegand_formatutils.c
+++ b/client/src/wiegand_formatutils.c
@@ -64,7 +64,7 @@ bool set_bit_by_position(wiegand_message_t *data, bool value, uint8_t pos) {
  * If the definition of the wiegand_message struct changes, this function must also
  * be updated to match.
  */
-void message_datacopy(wiegand_message_t *src, wiegand_message_t *dest) {
+static void message_datacopy(wiegand_message_t *src, wiegand_message_t *dest) {
     dest->Bot = src->Bot;
     dest->Mid = src->Mid;
     dest->Top = src->Top;