meson: remove _ISOCXX_SOURCE macros on Windows

With a proper C11 compiler we don't need this. Either they activate C11
things in the compiler which should be there anyway. Or in the SDK
which is __USE_MINGW_ANSI_STDIO for C99 and nothing else.

config.h.meson

@@ -42,12 +42,6 @@
 /* Define for Windows 7 APIs. */
 #mesondefine _WIN32_WINNT
 
-/* Extensions to ISO C89 from ISO C99. */
-#mesondefine _ISOC99_SOURCE
-
-/* Extensions to ISO C99 from ISO C11. */
-#mesondefine _ISOC11_SOURCE
-
 /* IEEE Std 1003.1. */
 #mesondefine _POSIX_SOURCE
 

configure.ac

@@ -293,8 +293,6 @@ int foo() { return my_array[0]; }
     ])
     AC_DEFINE([WIN32_LEAN_AND_MEAN],, [Define to limit the scope of <windows.h>.])
     AC_DEFINE([UNICODE], [1], [Define to 1 for Unicode (Wide Chars) APIs.])
-    AC_DEFINE([_ISOC99_SOURCE], [1], [Extensions to ISO C89 from ISO C99.])
-    AC_DEFINE([_ISOC11_SOURCE], [1], [Extensions to ISO C99 from ISO C11.])
     AC_DEFINE([_POSIX_SOURCE], [1], [IEEE Std 1003.1.])
     AC_DEFINE([_POSIX_C_SOURCE], [200809L], [IEEE Std 1003.1.])
 

meson.build

@@ -343,8 +343,6 @@ windows_version_test = '''
 
         mingw_defines = [
             ['__USE_MINGW_ANSI_STDIO',      1], # Define to force use of MinGW printf
-            ['_ISOC99_SOURCE',              1], # Extensions to ISO C89 from ISO C99
-            ['_ISOC11_SOURCE',              1], # Extensions to ISO C99 from ISO C11
             ['_POSIX_SOURCE',               1], # IEEE Std 1003.1
             ['_POSIX_C_SOURCE',             '200809L'], #IEEE Std 1003.1
         ]