diff --git a/Makefile.libretro b/Makefile.libretro
index 9cab7e4bd79..0709a60f66a 100644
--- a/Makefile.libretro
+++ b/Makefile.libretro
@@ -277,7 +277,7 @@ else ifeq ($(platform), ps2)
    CC = mips64r5900el-ps2-elf-gcc$(EXE_EXT)
    AR = mips64r5900el-ps2-elf-ar$(EXE_EXT)
    PLATFORM_DEFINES := -DPS2 -DCC_RESAMPLER
-   CFLAGS += -G0 -DHAVE_NO_LANGEXTRA -DHAVE_STRTOF_L
+   CFLAGS += -G0 -DHAVE_NO_LANGEXTRA -DHAVE_STRTOF_L -D_GNU_SOURCE -DHAVE_LOCALE
    STATIC_LINKING = 1
    DEFINES += -std=c99
 	HAVE_VFS_FD = 0