[PATCH] D92384: [AST][NFC] Silence GCC warning about broken strict aliasing rules

Thomas Preud'homme via Phabricator via cfe-commits cfe-commits at lists.llvm.org
Fri Dec 4 06:35:04 PST 2020


This revision was automatically updated to reflect the committed changes.
Closed by commit rG507bbc45bba9: [AST][NFC] Silence GCC warning about broken strict aliasing rules (authored by thopre).

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D92384/new/

https://reviews.llvm.org/D92384

Files:
  clang/include/clang/AST/Attr.h


Index: clang/include/clang/AST/Attr.h
===================================================================
--- clang/include/clang/AST/Attr.h
+++ clang/include/clang/AST/Attr.h
@@ -259,7 +259,10 @@
 
   /// Construct from a result from \c serialize.
   static ParamIdx deserialize(SerialType S) {
-    ParamIdx P(*reinterpret_cast<ParamIdx *>(&S));
+    // Using this two-step static_cast via void * instead of reinterpret_cast
+    // silences a -Wstrict-aliasing false positive from GCC7 and earlier.
+    void *ParamIdxPtr = static_cast<void *>(&S);
+    ParamIdx P(*static_cast<ParamIdx *>(ParamIdxPtr));
     assert((!P.IsValid || P.Idx >= 1) && "valid Idx must be one-origin");
     return P;
   }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D92384.309528.patch
Type: text/x-patch
Size: 703 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20201204/5a9dfaba/attachment-0001.bin>


More information about the cfe-commits mailing list