[clang-tools-extra] [clang-tidy] Enable C99 in `implicit-bool-conversion` and avoid FP with `bool` operands in C23 (PR #171070)

[Yanzuo Liu via cfe-commits]

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@@ -27,7 +27,9 @@ AST_MATCHER(Stmt, isMacroExpansion) {
   return SM.isMacroBodyExpansion(Loc) || SM.isMacroArgExpansion(Loc);
 }
 
-AST_MATCHER(Stmt, isC23) { return Finder->getASTContext().getLangOpts().C23; }
+AST_MATCHER(Stmt, isC) {
+  return !Finder->getASTContext().getLangOpts().CPlusPlus;
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zwuis wrote:

What about `return .getLangOpts().C99`? We don't need to handle C89 in this check.

https://github.com/llvm/llvm-project/pull/171070