more stdlib includes

cbuild

@@ -1 +1 @@
-Subproject commit d72aa0c8098fe2a427e50355250f473d70886502
+Subproject commit 2bebe76c7e14155392a167bdda61113d0039e188

src/base/std.h

@@ -8,9 +8,12 @@ extern "C" {
 #include <stdlib.h>
 #include <stdint.h>
 #include <stdarg.h>
+#include <stddef.h>
 #include <locale.h>
 #include <time.h>
 #include <setjmp.h>
+#include <signal.h>
+#include <math.h>
 
 typedef int8_t i8;
 typedef uint8_t u8;