Revert "[analyzer; alternate edges] don't add an edge incoming from the start of a function"

...and make this work correctly in the current codebase.

After living on this for a while, it turns out to look very strange for
inlined functions that have only a single statement, and somewhat strange
for inlined functions in general (since they are still conceptually in the
middle of the path, and there is a function-entry path note).

It's worth noting that this only affects inlined functions; in the new
arrow generation algorithm, the top-level function still starts at the
first real statement in the function body, not the enclosing CompoundStmt.

This reverts r182078 / dbfa950abe0e55b173286a306ee620eff5f72ea.

llvm-svn: 182963

1 files changed, 8 insertions, 1 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
index fe830183fbb..2fb1a26cc2a 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -1557,7 +1557,7 @@ static void addEdgeToPath(PathPieces &path,
   if (NewLocL.isInvalid() || NewLocL.isMacroID())
     return;
 
-  if (!PrevLoc.isValid()) {
+  if (!PrevLoc.isValid() || !PrevLoc.asLocation().isValid()) {
     PrevLoc = NewLoc;
     return;
   }
@@ -1608,6 +1608,13 @@ GenerateAlternateExtensivePathDiagnostic(PathDiagnostic& PD,
       // call exit before this point.  This means that the path
       // terminated within the call itself.
       if (Optional<CallEnter> CE = P.getAs<CallEnter>()) {
+        // Add an edge to the start of the function.
+        const StackFrameContext *CalleeLC = CE->getCalleeContext();
+        const Decl *D = CalleeLC->getDecl();
+        addEdgeToPath(PD.getActivePath(), PrevLoc,
+                      PathDiagnosticLocation::createBegin(D, SM),
+                      CalleeLC);
+
         // Did we visit an entire call?
         bool VisitedEntireCall = PD.isWithinCall();
         PD.popActivePath();