[PATCH] D154130: [lit][clang] Avoid realpath on Windows due to MAX_PATH limitations

[Ben Langmuir via Phabricator via cfe-commits]

benlangmuir added inline comments.


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Comment at: clang/lib/Basic/FileManager.cpp:655
+  SmallString<4096> AbsPathBuf = Name;
+  SmallString<4096> RealPathBuf;
+  if (!FS->makeAbsolute(AbsPathBuf)) {
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8k is a lot of stack space. The only reason this was 4k in the first place is it was originally using `char[PATH_MAX]` and unix `realpath` directly.  I'd suggest just dropping to 128 per path.


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Comment at: clang/lib/Basic/FileManager.cpp:663
+    } else {
+      llvm::sys::path::remove_dots(AbsPathBuf, /*remove_dot_dot=*/true);
+      CanonicalName = AbsPathBuf.str().copy(CanonicalNameStorage);
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Removing .. can change where the path points in the presence of symlinks; is this needed?


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Comment at: clang/lib/ExtractAPI/ExtractAPIConsumer.cpp:190
 
-    StringRef FileName = File->tryGetRealPathName().empty()
-                             ? File->getName()
-                             : File->tryGetRealPathName();
+    StringRef FileName = SM.getFileManager().getCanonicalName(File);
 
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Why is this change needed?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D154130/new/

https://reviews.llvm.org/D154130