[clang-tidy] Exempt _MSVC_EXECUTION_CHARACTER_SET from cppcoreguidelines-macro-usage

[zero9178]

Summary

In https://reviews.llvm.org/D114576 I am trying to add an unconditional define to the MSVC cc1 driver which sadly then leads to a test failure in cppcoreguidelines-macro-usage-command-line-macros.cpp with MSVC builds.

The solution is a bit hacky IMO, but there seems to already be a similar workaround for __GCC_HAVE_DWARF2_CFI_ASM. I don't know of any way to differentiate between defines passed on the CLI by users, and ones set by the driver, so this will have to do for now.

[lebedev.ri]

clang-tools-extra/clang-tidy/cppcoreguidelines/MacroUsageCheck.cpp

40

Can that macro be defined elsewhere so this check fires instead of having to special-case the macro here?

[zero9178]

Found another solution to the original issue

clang-tools-extra/clang-tidy/cppcoreguidelines/MacroUsageCheck.cpp

 class MacroUsageCallbacks : public PPCallbacks {
 public:
   MacroUsageCallbacks(MacroUsageCheck *Check, const SourceManager &SM,
                       StringRef RegExpStr, bool CapsOnly, bool IgnoreCommandLine)
       : Check(Check), SM(SM), RegExp(RegExpStr), CheckCapsOnly(CapsOnly),
         IgnoreCommandLineMacros(IgnoreCommandLine) {}
   void MacroDefined(const Token &MacroNameTok,
                     const MacroDirective *MD) override {
     if (SM.isWrittenInBuiltinFile(MD->getLocation()) ||
         MD->getMacroInfo()->isUsedForHeaderGuard() ||
         MD->getMacroInfo()->getNumTokens() == 0)
       return;
 
     if (IgnoreCommandLineMacros &&
         SM.isWrittenInCommandLineFile(MD->getLocation()))
       return;
 
     StringRef MacroName = MacroNameTok.getIdentifierInfo()->getName();
-    if (MacroName == "__GCC_HAVE_DWARF2_CFI_ASM")
+    if (MacroName == "__GCC_HAVE_DWARF2_CFI_ASM" ||
+        MacroName == "_MSVC_EXECUTION_CHARACTER_SET")
       return;
     if (!CheckCapsOnly && !RegExp.match(MacroName))
       Check->warnMacro(MD, MacroName);
 
     if (CheckCapsOnly && !isCapsOnly(MacroName))
       Check->warnNaming(MD, MacroName);
   }