Relax assertion in CFG builder when processing ForStmts. This fixes an assertion failure

on code containing GNU statement expressions reported in PR 8141.

llvm-svn: 113953

2 files changed, 8 insertions, 1 deletions

diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp
index e297ec4856c..cc3a3888626 100644
--- a/clang/lib/Analysis/CFG.cpp
+++ b/clang/lib/Analysis/CFG.cpp
@@ -991,7 +991,8 @@ CFGBlock* CFGBuilder::VisitForStmt(ForStmt* F) {
   if (Stmt* C = F->getCond()) {
     Block = ExitConditionBlock;
     EntryConditionBlock = addStmt(C);
-    assert(Block == EntryConditionBlock);
+    assert(Block == EntryConditionBlock ||
+           (Block == 0 && EntryConditionBlock == Succ));
 
     // If this block contains a condition variable, add both the condition
     // variable and initializer to the CFG.
diff --git a/clang/test/Analysis/misc-ps.m b/clang/test/Analysis/misc-ps.m
index a44eb0c18d3..bb70c90e6a6 100644
--- a/clang/test/Analysis/misc-ps.m
+++ b/clang/test/Analysis/misc-ps.m
@@ -1129,3 +1129,9 @@ void rdar6351970_c() {
 }
 @end
 
+// PR 8149 - GNU statement expression in condition of ForStmt.
+// This previously triggered an assertion failure in CFGBuilder.
+void pr8149(void) {
+  for (; ({ do { } while (0); 0; });) { }
+}
+