From 3abbe613661cfb917540788fb96870efa2b3c4ca Mon Sep 17 00:00:00 2001
From: Moritz Warning <moritzwarning@web.de>
Date: Thu, 22 Jan 2015 22:24:39 +0100
Subject: [PATCH] allow use of environment variables to set/extend CC, CXX,
 CFLAGS and LDFLAGS

---
 make-freebsd.mk | 15 ++++++++-------
 make-linux.mk   | 15 ++++++++-------
 make-mac.mk     | 11 ++++++-----
 3 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/make-freebsd.mk b/make-freebsd.mk
index 2eea8eafb..e57859e4c 100644
--- a/make-freebsd.mk
+++ b/make-freebsd.mk
@@ -1,5 +1,5 @@
-CC=cc
-CXX=c++
+CC?=cc
+CXX?=c++
 
 INCLUDES=
 DEFS=
@@ -21,15 +21,16 @@ endif
 # "make debug" is a shortcut for this
 ifeq ($(ZT_DEBUG),1)
 #	DEFS+=-DZT_TRACE -DZT_LOG_STDOUT 
-	CFLAGS=-Wall -g -pthread $(INCLUDES) $(DEFS)
-	LDFLAGS=
+	CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
+	LDFLAGS+=
 	STRIP=echo
 	# The following line enables optimization for the crypto code, since
 	# C25519 in particular is almost UNUSABLE in heavy testing without it.
-ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS = -Wall -O2 -g -pthread $(INCLUDES) $(DEFS)
+ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS?=-O2 CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
 else
-	CFLAGS=-Wall -O3 -fPIE -fvisibility=hidden -fstack-protector -pthread $(INCLUDES) -DNDEBUG $(DEFS)
-	LDFLAGS=-pie -Wl,-z,relro,-z,now
+	CFLAGS?=-O3
+	CFLAGS+=-Wall -fPIE -fvisibility=hidden -fstack-protector -pthread $(INCLUDES) -DNDEBUG $(DEFS)
+	LDFLAGS+=-pie -Wl,-z,relro,-z,now
 	STRIP=strip --strip-all
 endif
 
diff --git a/make-linux.mk b/make-linux.mk
index e0951711a..58a38dbde 100644
--- a/make-linux.mk
+++ b/make-linux.mk
@@ -1,6 +1,6 @@
 # Pick clang or gcc, with preference for clang
-CC=$(shell which clang gcc cc 2>/dev/null | head -n 1)
-CXX=$(shell which clang++ g++ c++ 2>/dev/null | head -n 1)
+CC?=$(shell which clang gcc cc 2>/dev/null | head -n 1)
+CXX?=$(shell which clang++ g++ c++ 2>/dev/null | head -n 1)
 
 INCLUDES=
 DEFS=
@@ -22,15 +22,16 @@ endif
 # "make debug" is a shortcut for this
 ifeq ($(ZT_DEBUG),1)
 #	DEFS+=-DZT_TRACE -DZT_LOG_STDOUT 
-	CFLAGS=-Wall -g -pthread $(INCLUDES) $(DEFS)
-	LDFLAGS=
+	CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
+	LDFLAGS+=
 	STRIP=echo
 	# The following line enables optimization for the crypto code, since
 	# C25519 in particular is almost UNUSABLE in heavy testing without it.
-ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS = -Wall -O2 -g -pthread $(INCLUDES) $(DEFS)
+ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS?=-O2 CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
 else
-	CFLAGS=-Wall -O3 -fPIE -fvisibility=hidden -fstack-protector -pthread $(INCLUDES) -DNDEBUG $(DEFS)
-	LDFLAGS=-pie -Wl,-z,relro,-z,now
+	CFLAGS?=-O3
+	CFLAGS+=-Wall -fPIE -fvisibility=hidden -fstack-protector -pthread $(INCLUDES) -DNDEBUG $(DEFS)
+	LDFLAGS+=-pie -Wl,-z,relro,-z,now -static-libstdc++
 	STRIP=strip --strip-all
 endif
 
diff --git a/make-mac.mk b/make-mac.mk
index 854990bb9..d6adec426 100644
--- a/make-mac.mk
+++ b/make-mac.mk
@@ -1,5 +1,5 @@
-CC=clang
-CXX=clang++
+CC?=clang
+CXX?=clang++
 
 INCLUDES=
 DEFS=
@@ -27,13 +27,14 @@ endif
 
 ifeq ($(ZT_DEBUG),1)
 #	DEFS+=-DZT_TRACE -DZT_LOG_STDOUT 
-	CFLAGS=-Wall -g -pthread $(INCLUDES) $(DEFS)
+	CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
 	STRIP=echo
 	# The following line enables optimization for the crypto code, since
 	# C25519 in particular is almost UNUSABLE in heavy testing without it.
-ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS = -Wall -O2 -g -pthread $(INCLUDES) $(DEFS)
+ext/lz4/lz4.o node/Salsa20.o node/SHA512.o node/C25519.o node/Poly1305.o: CFLAGS?=-O2 CFLAGS+=-Wall -g -pthread $(INCLUDES) $(DEFS)
 else
-	CFLAGS=-arch i386 -arch x86_64 -Wall -O3 -flto -fPIE -fvectorize -fstack-protector -pthread -mmacosx-version-min=10.6 -DNDEBUG -Wno-unused-private-field $(INCLUDES) $(DEFS)
+	CFLAGS?=-O3
+	CFLAGS+=-arch i386 -arch x86_64 -Wall -flto -fPIE -fvectorize -fstack-protector -pthread -mmacosx-version-min=10.6 -DNDEBUG -Wno-unused-private-field $(INCLUDES) $(DEFS)
 	STRIP=strip
 endif