Define HAVE_LIBC for the platforms with a C library

Allow the Visual Studio project to define HAVE_LIBC=0 to enable building without a C runtime on Windows entirely through Visual Studio project changes.

include/build_config/SDL_build_config_android.h

@@ -52,6 +52,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_DLOPEN 1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1

include/build_config/SDL_build_config_emscripten.h

@@ -55,6 +55,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_DLOPEN 1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1

include/build_config/SDL_build_config_ios.h

@@ -44,6 +44,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_DLOPEN 1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1

include/build_config/SDL_build_config_macos.h

@@ -49,6 +49,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_DLOPEN 1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1

include/build_config/SDL_build_config_windows.h

@@ -112,8 +112,11 @@ typedef unsigned int uintptr_t;
 #endif
 
 /* This can be disabled to avoid C runtime dependencies and manifest requirements */
-#define HAVE_LIBC
-#ifdef HAVE_LIBC
+#ifndef HAVE_LIBC
+#define HAVE_LIBC   1
+#endif
+
+#if HAVE_LIBC
 /* Useful headers */
 #define HAVE_CTYPE_H 1
 #define HAVE_FLOAT_H 1

include/build_config/SDL_build_config_wingdk.h

@@ -56,8 +56,6 @@
 # define SDL_DISABLE_AVX 1
 #endif
 
-/* This is disabled by default to avoid C runtime dependencies and manifest requirements */
-#ifdef HAVE_LIBC
 /* Useful headers */
 #define HAVE_CTYPE_H 1
 #define HAVE_FLOAT_H 1
@@ -73,6 +71,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1
 #define HAVE_REALLOC 1
@@ -156,11 +155,6 @@
 #define HAVE_TRUNCF 1
 #define HAVE__FSEEKI64 1
 #endif    /* _MSC_VER */
-#else
-#define HAVE_STDARG_H   1
-#define HAVE_STDDEF_H   1
-#define HAVE_STDINT_H   1
-#endif
 
 /* Enable various audio drivers */
 #if defined(HAVE_MMDEVICEAPI_H) && defined(HAVE_AUDIOCLIENT_H)

include/build_config/SDL_build_config_winrt.h

@@ -71,6 +71,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1
 #define HAVE_REALLOC 1

include/build_config/SDL_build_config_xbox.h

@@ -56,8 +56,6 @@
 # define SDL_DISABLE_AVX 1
 #endif
 
-/* This is disabled by default to avoid C runtime dependencies and manifest requirements */
-#ifdef HAVE_LIBC
 /* Useful headers */
 #define HAVE_CTYPE_H 1
 #define HAVE_FLOAT_H 1
@@ -73,6 +71,7 @@
 #define HAVE_WCHAR_H 1
 
 /* C library functions */
+#define HAVE_LIBC   1
 #define HAVE_MALLOC 1
 #define HAVE_CALLOC 1
 #define HAVE_REALLOC 1
@@ -156,11 +155,6 @@
 #define HAVE_TRUNCF 1
 #define HAVE__FSEEKI64 1
 #endif    /* _MSC_VER */
-#else
-#define HAVE_STDARG_H   1
-#define HAVE_STDDEF_H   1
-#define HAVE_STDINT_H   1
-#endif
 
 /* Enable various audio drivers */
 #if defined(HAVE_MMDEVICEAPI_H) && defined(HAVE_AUDIOCLIENT_H)