[clang] [Clang] [Sema] Allow non-local/non-variable declarations in for loop (PR #129737)

[Shafik Yaghmour via cfe-commits]

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@@ -1,13 +1,21 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -verify=c11 -std=c11 -pedantic %s
+// RUN: %clang_cc1 -fsyntax-only -verify=c23 -std=c23 -Wpre-c23-compat %s
 
 // Check C99 6.8.5p3
 void b1 (void) { for (void (*f) (void);;); }
-void b2 (void) { for (void f (void);;); }   // expected-error {{non-variable declaration in 'for' loop}}
-void b3 (void) { for (static int f;;); }    // expected-error {{declaration of non-local variable}}
-void b4 (void) { for (typedef int f;;); }   // expected-error {{non-variable declaration in 'for' loop}}
+void b2 (void) { for (void f (void);;); }   /* c11-warning {{non-variable declaration in 'for' loop is a C23 extension}}
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shafik wrote:

Apologies for the drive by after commit review but I really would like to see that. Having spent some time digging into regression the past few months a main pattern is lack of testing and so I am trying to push asking for more in the testing arena.

https://github.com/llvm/llvm-project/pull/129737