[clang] [clang] Catch missing format attributes (PR #70024)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-win-x-aarch64` running on `as-builder-2` while building `clang` at step 9 "test-check-clang".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/193/builds/896

Here is the relevant piece of the build log for the reference:
```
Step 9 (test-check-clang) failure: Test just built components for check-clang completed (failure)
******************** TEST 'Clang :: Sema/attr-format-missing.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
c:\buildbot\as-builder-2\x-aarch64\build\bin\clang.exe -cc1 -internal-isystem C:\buildbot\as-builder-2\x-aarch64\build\lib\clang\19\include -nostdsysteminc -fsyntax-only -verify=expected,c_diagnostics -Wmissing-format-attribute C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c
# executed command: 'c:\buildbot\as-builder-2\x-aarch64\build\bin\clang.exe' -cc1 -internal-isystem 'C:\buildbot\as-builder-2\x-aarch64\build\lib\clang\19\include' -nostdsysteminc -fsyntax-only -verify=expected,c_diagnostics -Wmissing-format-attribute 'C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c'
# .---command stderr------------
# | error: 'c_diagnostics-error' diagnostics seen but not expected: 
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 87: subscripted value is not an array, pointer, or vector
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 95: subscripted value is not an array, pointer, or vector
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 96: subscripted value is not an array, pointer, or vector
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 391: passing 'char *' to parameter of incompatible type '__builtin_va_list'
# | error: 'c_diagnostics-warning' diagnostics expected but not seen: 
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 83 (directive at C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c:87): diagnostic behavior may be improved by adding the 'scanf' format attribute to the declaration of 'f7'
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 111 (directive at C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c:113): incompatible pointer types passing 'const wchar_t *' (aka 'const int *') to parameter of type 'const char *'
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 141 (directive at C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c:143): incompatible pointer types passing 'const wchar_t *' (aka 'const int *') to parameter of type 'const char *'
# | error: 'c_diagnostics-warning' diagnostics seen but not expected: 
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 111: incompatible pointer types passing 'const wchar_t *' (aka 'const unsigned int *') to parameter of type 'const char *'
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 141: incompatible pointer types passing 'const wchar_t *' (aka 'const unsigned int *') to parameter of type 'const char *'
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 387: diagnostic behavior may be improved by adding the 'printf' format attribute to the declaration of 'f41'
# | error: 'c_diagnostics-note' diagnostics seen but not expected: 
# |   File C:\buildbot\as-builder-2\x-aarch64\llvm-project\clang\test\Sema\attr-format-missing.c Line 30: passing argument to parameter here
# | 11 errors generated.
# `-----------------------------
# error: command failed with exit status: 1

--

********************


```

https://github.com/llvm/llvm-project/pull/70024