[clang] [llvm] [Sema] Implement support for -Wformat-signedness (PR #74440)

[Karl-Johan Karlsson via llvm-commits]

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+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -std=c11 -fsyntax-only -verify -Wformat -Wformat-signedness %s
+// RUN: %clang_cc1 -triple=x86_64-pc-win32 -std=c11 -fsyntax-only -verify -Wformat -Wformat-signedness %s
+
+// Verify that -Wformat-signedness alone (without -Wformat) trigger the
+// warnings. Note in gcc this will not trigger the signedness warnings as
+// -Wformat is default off in gcc.
+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -std=c11 -fsyntax-only -verify -Wformat-signedness %s
+// RUN: %clang_cc1 -triple=x86_64-pc-win32 -std=c11 -fsyntax-only -verify -Wformat-signedness %s
+
+// Verify that -Wformat-signedness warnings are not reported with only -Wformat
+// (gcc compat).
+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -std=c11 -fsyntax-only -Wformat -Werror %s
+
+// Verify that -Wformat-signedness with -Wno-format are not reported (gcc compat).
+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -std=c11 -fsyntax-only -Wformat-signedness -Wno-format -Werror %s
+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -std=c11 -fsyntax-only -Wno-format -Wformat-signedness -Werror %s
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karka228 wrote:

Ohh, I didn't know that you could supply a prefix to `-verify`.  I will fix this.

https://github.com/llvm/llvm-project/pull/74440