diff -r 6961c662493c CMakeLists.txt
--- a/CMakeLists.txt	Mon Aug 03 11:37:03 2015 -0700
+++ b/CMakeLists.txt	Sun Dec 06 11:27:18 2015 +0100
@@ -533,6 +533,7 @@
 # TODO: Can't deactivate on FreeBSD? w/o LIBC, SDL_stdinc.h can't define
 # anything.
 if(LIBC)
+  set(STDC_HEADERS 1)
   if(WINDOWS AND NOT MINGW)
     set(HAVE_LIBC TRUE)
     foreach(_HEADER stdio.h string.h ctype.h math.h)
@@ -555,7 +556,6 @@
     endif()
     set(HAVE_M_PI 1)
     add_definitions(-D_USE_MATH_DEFINES) # needed for M_PI
-    set(STDC_HEADERS 1)
   else()
     set(HAVE_LIBC TRUE)
     check_include_file(sys/types.h HAVE_SYS_TYPES_H)