diff --git a/ggml.h b/ggml.h
index bac4fe65c7ad5..da5f47a685f95 100644
--- a/ggml.h
+++ b/ggml.h
@@ -177,6 +177,7 @@ extern "C" {
 #include <stddef.h>
 #include <stdbool.h>
 
+#define __USE_POSIX199309 1
 #define GGML_MAX_DIMS     4
 #define GGML_MAX_NODES    4096
 #define GGML_MAX_PARAMS   16