Add -fno-strict-aliasing workaround for all GCC targets

Use a GCC option to work around aliasing bugs. See commit 013dbcd for
more details.
diff --git a/configs/darwin b/configs/darwin
index 7826ecc..76f3f74 100644
--- a/configs/darwin
+++ b/configs/darwin
@@ -10,6 +10,10 @@
 CFLAGS = -I/usr/X11R6/include -O3 -fPIC -fno-common -ffast-math -funroll-loops -fexpensive-optimizations -no-cpp-precomp -dynamic -Ddarwin
 CXXFLAGS = -I/usr/X11R6/include -O3 -fPIC -fno-common -ffast-math -funroll-loops -fexpensive-optimizations -no-cpp-precomp -dynamic -Ddarwin
 
+# Work around aliasing bugs - developers should comment this out
+CFLAGS += -fno-strict-aliasing
+CXXFLAGS += -fno-strict-aliasing
+
 # Library names (actual file names)
 GL_LIB_NAME = libGL.dylib
 GLU_LIB_NAME = libGLU.dylib