[clang] Add Clang attribute to ensure that fields are initialized explicitly (PR #102040)

[via cfe-commits]

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@@ -1682,7 +1690,7 @@ class DeclContext {
 
     /// True if a valid hash is stored in ODRHash. This should shave off some
     /// extra storage and prevent CXXRecordDecl to store unused bits.
-    uint64_t ODRHash : 26;
+    uint64_t ODRHash : 25;
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higher-performance wrote:

Fixed this, thanks for the catch! I'm not sure how to measure it (I don't even know what it's for!) but if someone comes up with an easy way feel free to let me know.

https://github.com/llvm/llvm-project/pull/102040