[PATCH] D154784: [clang] Fix crash caused by PseudoObjectExprBitfields::NumSubExprs overflow

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yronglin updated this revision to Diff 539493.
yronglin added a comment.

Address comment


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D154784/new/

https://reviews.llvm.org/D154784

Files:
  clang/docs/ReleaseNotes.rst
  clang/include/clang/AST/Stmt.h
  clang/test/SemaCXX/builtin-dump-struct.cpp


Index: clang/test/SemaCXX/builtin-dump-struct.cpp
===================================================================
--- clang/test/SemaCXX/builtin-dump-struct.cpp
+++ clang/test/SemaCXX/builtin-dump-struct.cpp
@@ -159,3 +159,28 @@
                                         // expected-note@#Format {{no known conversion from 'int' to 'ConstexprString &' for 1st argument}}
 }
 #endif
+
+// Check that PseudoObjectExprBitfields:NumSubExprs doesn't overflow. This
+// would previously cause a crash.
+struct t1 {
+  int v0, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16,
+      v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31,
+      v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46,
+      v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61,
+      v62, v63, v64, v65, v66, v67, v68, v69, v70, v71, v72, v73, v74, v75, v76,
+      v77, v78, v79, v80, v81, v82, v83, v84, v85, v86, v87, v88, v89, v90, v91,
+      v92, v93, v94, v95, v96, v97, v98, v99;
+};
+
+struct t2 {
+  t1 v0, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16,
+      v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31,
+      v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46,
+      v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61,
+      v62, v63, v64, v65, v66, v67, v68, v69, v70, v71, v72, v73, v74, v75, v76,
+      v77, v78, v79, v80, v81, v82, v83, v84, v85, v86, v87, v88, v89, v90, v91,
+      v92, v93, v94, v95, v96, v97, v98, v99;
+};
+
+int printf(const char *, ...);
+void f1(t2 w) { __builtin_dump_struct(&w, printf); }
Index: clang/include/clang/AST/Stmt.h
===================================================================
--- clang/include/clang/AST/Stmt.h
+++ clang/include/clang/AST/Stmt.h
@@ -593,10 +593,8 @@
 
     unsigned : NumExprBits;
 
-    // These don't need to be particularly wide, because they're
-    // strictly limited by the forms of expressions we permit.
-    unsigned NumSubExprs : 8;
-    unsigned ResultIndex : 32 - 8 - NumExprBits;
+    unsigned NumSubExprs : 16;
+    unsigned ResultIndex : 16;
   };
 
   class SourceLocExprBitfields {
Index: clang/docs/ReleaseNotes.rst
===================================================================
--- clang/docs/ReleaseNotes.rst
+++ clang/docs/ReleaseNotes.rst
@@ -591,6 +591,8 @@
   (`#38717 <https://github.com/llvm/llvm-project/issues/38717>_`).
 - Fix an assertion when using ``\u0024`` (``$``) as an identifier, by disallowing
   that construct (`#62133 <https://github.com/llvm/llvm-project/issues/38717>_`).
+- Fix crash caused by PseudoObjectExprBitfields: NumSubExprs overflow.
+  (`#63169 <https://github.com/llvm/llvm-project/issues/63169>_`)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


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