Restore Check for Unreachable Exit Block in -Winfinite-recursion

Summary:
When this was rewritten in D43737, the logic changed to better explore infinite loops. The check for a reachable exit block was deleted which accidentally introduced false positives in case the exit node was unreachable.

We were testing for cases like this, but @steven_wu provided an additional test case that I've included in the regression tests for this patch.

Reviewers: steven_wu, rtrieu

Reviewed By: steven_wu, rtrieu

Subscribers: cfe-commits, steven_wu

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58122

llvm-svn: 353984

1 files changed, 11 insertions, 2 deletions

diff --git a/clang/test/SemaCXX/warn-infinite-recursion.cpp b/clang/test/SemaCXX/warn-infinite-recursion.cpp
index bbeff92a657..e5a5a18b657 100644
--- a/clang/test/SemaCXX/warn-infinite-recursion.cpp
+++ b/clang/test/SemaCXX/warn-infinite-recursion.cpp
@@ -53,19 +53,28 @@ int j() {  // expected-warning{{call itself}}
   return 5 + j();
 }
 
-void k() {  // expected-warning{{call itself}}
+// Don't warn on infinite loops
+void k() {
   while(true) {
     k();
   }
 }
 
-// Don't warn on infinite loops
 void l() {
   while (true) {}
 
   l();
 }
 
+void m() {
+  static int count = 5;
+  if (count >0) {
+    count--;
+    l();
+  }
+  while (true) {}
+}
+
 class S {
   static void a();
   void b();