Fix for va_copy.

upb/pb/textprinter.c

@@ -96,10 +96,6 @@ static int putescaped(upb_textprinter *p, const char *buf, size_t len,
   return 0;
 }
 
-#ifdef __GNUC__
-#define va_copy(a, b) __va_copy(a, b)
-#endif
-
 bool putf(upb_textprinter *p, const char *fmt, ...) {
   va_list args;
   va_list args_copy;
@@ -111,7 +107,7 @@ bool putf(upb_textprinter *p, const char *fmt, ...) {
   va_start(args, fmt);
 
   /* Run once to get the length of the string. */
-  va_copy(args_copy, args);
+  _upb_va_copy(args_copy, args);
   len = _upb_vsnprintf(NULL, 0, fmt, args_copy);
   va_end(args_copy);
 

upb/upb.h

@@ -52,12 +52,14 @@
 #ifdef __GNUC__
 #define _upb_snprintf __builtin_snprintf
 #define _upb_vsnprintf __builtin_vsnprintf
+#define _upb_va_copy(a, b) __va_copy(a, b)
 #elif __STDC_VERSION__ >= 199901L
 /* C99 versions. */
 #define _upb_snprintf snprintf
 #define _upb_vsnprintf vsnprintf
+#define _upb_va_copy(a, b) va_copy(a, b)
 #else
-#error Need implementations of [v]snprintf
+#error Need implementations of [v]snprintf and va_copy
 #endif