r342766 - [analyzer] Fix bug in isInevitablySinking

[George Karpenkov via cfe-commits]

Author: george.karpenkov
Date: Fri Sep 21 13:36:01 2018
New Revision: 342766

URL: http://llvm.org/viewvc/llvm-project?rev=342766&view=rev
Log:
[analyzer] Fix bug in isInevitablySinking

If the non-sink report is generated at the exit node, it will be
suppressed by the current functionality in isInevitablySinking, as it
only checks the successors of the block, but not the block itself.

The bug shows up in RetainCountChecker checks.

Differential Revision: https://reviews.llvm.org/D52284

Modified:
    cfe/trunk/lib/StaticAnalyzer/Core/BugReporter.cpp

Modified: cfe/trunk/lib/StaticAnalyzer/Core/BugReporter.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Core/BugReporter.cpp?rev=342766&r1=342765&r2=342766&view=diff
==============================================================================
--- cfe/trunk/lib/StaticAnalyzer/Core/BugReporter.cpp (original)
+++ cfe/trunk/lib/StaticAnalyzer/Core/BugReporter.cpp Fri Sep 21 13:36:01 2018
@@ -2812,16 +2812,15 @@ static bool isInevitablySinking(const Ex
     DFSWorkList.pop_back();
     Visited.insert(Blk);
 
+    // If at least one path reaches the CFG exit, it means that control is
+    // returned to the caller. For now, say that we are not sure what
+    // happens next. If necessary, this can be improved to analyze
+    // the parent StackFrameContext's call site in a similar manner.
+    if (Blk == &Cfg.getExit())
+      return false;
+
     for (const auto &Succ : Blk->succs()) {
       if (const CFGBlock *SuccBlk = Succ.getReachableBlock()) {
-        if (SuccBlk == &Cfg.getExit()) {
-          // If at least one path reaches the CFG exit, it means that control is
-          // returned to the caller. For now, say that we are not sure what
-          // happens next. If necessary, this can be improved to analyze
-          // the parent StackFrameContext's call site in a similar manner.
-          return false;
-        }
-
         if (!isImmediateSinkBlock(SuccBlk) && !Visited.count(SuccBlk)) {
           // If the block has reachable child blocks that aren't no-return,
           // add them to the worklist.