[analyzer][NFC] Make sure that the BugReport is not modified during the construction of non-visitor pieces

I feel this is kinda important, because in a followup patch I'm adding different
kinds of interestingness, and propagating the correct kind in BugReporter.cpp is
just one less thing to worry about.

Differential Revision: https://reviews.llvm.org/D65578

llvm-svn: 368755

1 files changed, 12 insertions, 9 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
index 92d35b96692..f2983b7f4b6 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -192,13 +192,17 @@ public:
 };
 
 /// Contains every contextual information needed for constructing a
-/// PathDiagnostic object for a given bug report. This class (and aside from
-/// some caching BugReport does in the background) and its fields are immutable,
-/// and passes a BugReportConstruct object around during the construction.
+/// PathDiagnostic object for a given bug report. This class and its fields are
+/// immutable, and passes a BugReportConstruct object around during the
+/// construction.
 class PathDiagnosticBuilder : public BugReporterContext {
   /// A linear path from the error node to the root.
   std::unique_ptr<const ExplodedGraph> BugPath;
-  BugReport *R;
+  /// The bug report we're describing. Visitors create their diagnostics with
+  /// them being the last entities being able to modify it (for example,
+  /// changing interestingness here would cause inconsistencies as to how this
+  /// file and visitors construct diagnostics), hence its const.
+  const BugReport *R;
   /// The leaf of the bug path. This isn't the same as the bug reports error
   /// node, which refers to the *original* graph, not the bug path.
   const ExplodedNode *const ErrorNode;
@@ -257,7 +261,7 @@ private:
   ExecutionContinues(llvm::raw_string_ostream &os,
                      const PathDiagnosticConstruct &C) const;
 
-  BugReport *getBugReport() const { return R; }
+  const BugReport *getBugReport() const { return R; }
 };
 
 } // namespace
@@ -2172,14 +2176,13 @@ const Stmt *BugReport::getStmt() const {
   return S;
 }
 
-llvm::iterator_range<BugReport::ranges_iterator> BugReport::getRanges() {
+llvm::iterator_range<BugReport::ranges_iterator> BugReport::getRanges() const {
   // If no custom ranges, add the range of the statement corresponding to
   // the error node.
   if (Ranges.empty()) {
     if (const auto *E = dyn_cast_or_null<Expr>(getStmt()))
-      addRange(E->getSourceRange());
-    else
-      return llvm::make_range(ranges_iterator(), ranges_iterator());
+      return llvm::make_range(&ErrorNodeRange, &ErrorNodeRange + 1);
+    return llvm::make_range(ranges_iterator(), ranges_iterator());
   }
 
   // User-specified absence of range info.