macos compile nit.

[Janne Johansson]

gcc (actually clang) didn't like c++ options,
$ make
g++ -o lib/posit.o -std=c++11 -Ilib -Itest -O2 -Wall -g -c lib/posit.cpp
gcc -o lib/pack.o -std=c++11 -Ilib -Itest -O2 -Wall -g -c lib/pack.c
error: invalid argument '-std=c++11' not allowed with 'C/ObjC'

diff --git a/Makefile b/Makefile
index d9514a3..0a30df8 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
CC = gcc
CXX = g++
-CFLAGS = -std=c++11 -Ilib -Itest -O2 -Wall -g
-CXXFLAGS = $(CFLAGS)
+CFLAGS = -Ilib -Itest -O2 -Wall -g
+CXXFLAGS = $(CFLAGS) -std=c++11

LIB_TARGET = lib/libbfp.a

[Clément Guérin]

Should be fixed by e3b8c04. Feel free to reopen if needed. Thanks!