[PATCH] D97849: [AST][PCH][ASTImporter] Fix UB caused by uninited SwitchStmt member

[Gabor Marton via Phabricator via cfe-commits]

martong updated this revision to Diff 328149.
martong added a comment.
Herald added a reviewer: Szelethus.

Add a test case which fails if lit --vg is used.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97849/new/

https://reviews.llvm.org/D97849

Files:
  clang/include/clang/AST/Stmt.h
  clang/test/Analysis/Inputs/ctu-other.c
  clang/test/Analysis/Inputs/ctu-other.c.externalDefMap.ast-dump.txt
  clang/test/Analysis/ctu-main.c


Index: clang/test/Analysis/ctu-main.c
===================================================================
--- clang/test/Analysis/ctu-main.c
+++ clang/test/Analysis/ctu-main.c
@@ -69,3 +69,8 @@
   d.b = 0;
   clang_analyzer_eval(structInProto(&d) == 0); // expected-warning{{TRUE}} expected-warning{{FALSE}}
 }
+
+int switchWithoutCases(int);
+void testSwitchStmtCrash(int x) {
+  switchWithoutCases(x);
+}
Index: clang/test/Analysis/Inputs/ctu-other.c.externalDefMap.ast-dump.txt
===================================================================
--- clang/test/Analysis/Inputs/ctu-other.c.externalDefMap.ast-dump.txt
+++ clang/test/Analysis/Inputs/ctu-other.c.externalDefMap.ast-dump.txt
@@ -4,3 +4,4 @@
 c:@F at enumCheck ctu-other.c.ast
 c:@F at identImplicit ctu-other.c.ast
 c:@F at structInProto ctu-other.c.ast
+c:@F at switchWithoutCases ctu-other.c.ast
Index: clang/test/Analysis/Inputs/ctu-other.c
===================================================================
--- clang/test/Analysis/Inputs/ctu-other.c
+++ clang/test/Analysis/Inputs/ctu-other.c
@@ -49,3 +49,9 @@
 int structInProto(struct DataType {int a;int b; } * d) {
   return 0;
 }
+
+int switchWithoutCases(int x) {
+  switch (x) {
+  };
+  return 0;
+}
Index: clang/include/clang/AST/Stmt.h
===================================================================
--- clang/include/clang/AST/Stmt.h
+++ clang/include/clang/AST/Stmt.h
@@ -2119,7 +2119,7 @@
   friend TrailingObjects;
 
   /// Points to a linked list of case and default statements.
-  SwitchCase *FirstCase;
+  SwitchCase *FirstCase = nullptr;
 
   // SwitchStmt is followed by several trailing objects,
   // some of which optional. Note that it would be more convenient to


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