Fix Issue 12604 - Use a proper no-op macro expansion for VTRACE macro in _sre.c
diff --git a/Modules/_sre.c b/Modules/_sre.c
index 200e8dd..cd95917 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -2744,7 +2744,7 @@
 #if defined(VVERBOSE)
 #define VTRACE(v) printf v
 #else
-#define VTRACE(v)
+#define VTRACE(v) do {} while(0)  /* do nothing */
 #endif
 
 /* Report failure */