Merge pull request #873 from raingloom/patch-1

make it easier to set the compiler

Makefile

@@ -14,6 +14,7 @@ BINDIR ?= $(PREFIX)/bin
 MANDIR ?= $(PREFIX)/share/man/man1
 DOCDIRS = doc/html doc/latex
 PDF = doc/latex/refman.pdf
+CC ?= cc
 
 CFLAGS += -Wall -Wextra
 
@@ -46,7 +47,7 @@ slowtest: $(MININET)
 	mininet/examples/test/runner.py -v
 
 mnexec: mnexec.c $(MN) mininet/net.py
-	cc $(CFLAGS) $(LDFLAGS) -DVERSION=\"`PYTHONPATH=. $(PYMN) --version`\" $< -o $@
+	$(CC) $(CFLAGS) $(LDFLAGS) -DVERSION=\"`PYTHONPATH=. $(PYMN) --version`\" $< -o $@
 
 install-mnexec: $(MNEXEC)
 	install -D $(MNEXEC) $(BINDIR)/$(MNEXEC)