diff --git a/CHANGES b/CHANGES
index 398cd19..5f0f8ba 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2,7 +2,8 @@ Changelog for hydra
 -------------------
 
 Release 9.3-dev
-* New module: cobaltstrike by ultimaiiii, thank you!
+* support Xcode compilation
+* new module: cobaltstrike by ultimaiiii, thank you!
 * fix for ssh to support -M or ip/range
 * for vnc/cisco/... protocols that only check for a password, skip host
   after the password is found
diff --git a/Makefile.am b/Makefile.am
index 10cad3a..74288cf 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4,7 +4,7 @@
 WARN_CLANG=-Wformat-nonliteral -Wstrncat-size -Wformat-security -Wsign-conversion -Wconversion -Wfloat-conversion -Wshorten-64-to-32 -Wuninitialized -Wmissing-variable-declarations  -Wmissing-declarations
 WARN_GCC=-Wformat=2 -Wformat-overflow=2 -Wformat-nonliteral -Wformat-truncation=2 -Wnull-dereference -Wstrict-overflow=2 -Wstringop-overflow=4 -Walloca-larger-than=4096 -Wtype-limits -Wconversion -Wtrampolines -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -fno-common -Wcast-align
 CFLAGS ?= -g
-OPTS=-I. -O3 $(CFLAGS) -fcommon -Wl,--allow-multiple-definition
+OPTS=-I. -O3 $(CFLAGS) -fcommon
 # -Wall -g -pedantic
 LIBS=-lm
 DESTDIR ?=
diff --git a/configure b/configure
index 139c9bf..8ad8af2 100755
--- a/configure
+++ b/configure
@@ -1362,6 +1362,10 @@ echo '#include <strings.h>' >> $TMPC.c
 echo "int main() { char *x = strrchr(\"test\", 'e'); if (x == NULL) return 0; else return 1; }" >> $TMPC.c
 $CC -o $TMPC $TMPC.c > /dev/null 2>&1
 test -x $TMPC && STRRCHR=""
+rm -f $TMPC
+$CC -o $TMPC -Wl,--allow-multiple-definition $TMPC.c > /dev/null 2>&1
+WALLOW="no"
+test -x $TMPC && WALLOW="yes"
 rm -f $TMPC $TMPC.c
 echo "                                  ... strrchr()$STRRCHR found"
 if [ -n "$CRYPTO_PATH" ]; then
@@ -1392,6 +1396,11 @@ rm -f $TMPC $TMPC.c $TMPC.c.err
 echo "                                                  Compiling... $GCCSEC"
 echo "                                                  Linking... $LDSEC"
 
+echo "Checking for --allow-multiple-definition linker option ... $WALLOW"
+if [ "$WALLOW" = "yes" ]; then
+  GCCSECOPT="$GCCSECOPT -Wl,--allow-multiple-definition"
+fi
+
 echo
 XDEFINES=""
 XLIBS=""