[clang] [clang] Delay normalization of `-fmodules-cache-path` (PR #150123)

[Ben Langmuir via cfe-commits]

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@@ -547,10 +547,25 @@ void CompilerInstance::createPreprocessor(TranslationUnitKind TUKind) {
     PP->setDependencyDirectivesGetter(*GetDependencyDirectives);
 }
 
+SmallString<256>
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benlangmuir wrote:

It's usually preferable to use a `SmallVectorImpl<char> &` out parameter so the caller can decide the inline storage size

https://github.com/llvm/llvm-project/pull/150123