[clang] [clang] Diagnose config_macros before building modules (PR #83641)

[David Blaikie via cfe-commits]

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@@ -1591,6 +1591,14 @@ static void checkConfigMacro(Preprocessor &PP, StringRef ConfigMacro,
   }
 }
 
+static void checkConfigMacros(Preprocessor &PP, Module *M,
+                              SourceLocation ImportLoc) {
+  clang::Module *TopModule = M->getTopLevelModule();
+  for (unsigned I = 0, N = TopModule->ConfigMacros.size(); I != N; ++I) {
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dwblaikie wrote:

range based for loop?

https://github.com/llvm/llvm-project/pull/83641