Add some more diagnostics for va_start, fix tests so they pass with these new diags.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@42917 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/format-strings.c b/test/Sema/format-strings.c
index 83947cf..8b3be68 100644
--- a/test/Sema/format-strings.c
+++ b/test/Sema/format-strings.c
@@ -45,7 +45,7 @@
   printf("%\0d",1); // expected-warning {{string contains '\0'}}
 }
 
-void check_empty_format_string(char* buf)
+void check_empty_format_string(char* buf, ...)
 {
   va_list ap;
   va_start(ap,buf);
@@ -53,9 +53,8 @@
   sprintf(buf,""); // expected-warning {{format string is empty}}
 }
 
-void check_wide_string()
+void check_wide_string(char* b, ...)
 {
-  char *b;
   va_list ap;
   va_start(ap,b);