[PCH] Fix reading from PCH of diagnostic pragmas.

In certain cases ASTReader would call the normal DiagnosticsEngine API to initialize
the state of diagnostic pragmas but DiagnosticsEngine would try to compare source locations
leading to crash because the main FileID was not yet initialized.

Yet another case of the ASTReader trying to use the normal APIs and inadvertently breaking
invariants. Fix this by having the ASTReader set up the internal state directly.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@144153 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 7 insertions, 12 deletions

diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index e5f390196d..7ea296233a 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -169,18 +169,9 @@ void DiagnosticsEngine::setDiagnosticMapping(diag::kind Diag, diag::Mapping Map,
          "Cannot map errors into warnings!");
   assert(!DiagStatePoints.empty());
 
-  bool isPragma = L.isValid();
   FullSourceLoc Loc(L, *SourceMgr);
   FullSourceLoc LastStateChangePos = DiagStatePoints.back().Loc;
-  DiagnosticMappingInfo MappingInfo = DiagnosticMappingInfo::Make(
-    Map, /*IsUser=*/true, isPragma);
-
-  // If this is a pragma mapping, then set the diagnostic mapping flags so that
-  // we override command line options.
-  if (isPragma) {
-    MappingInfo.setNoWarningAsError(true);
-    MappingInfo.setNoErrorAsFatal(true);
-  }
+  DiagnosticMappingInfo MappingInfo = makeMappingInfo(Map, L);
 
   // Common case; setting all the diagnostics of a group in one place.
   if (Loc.isInvalid() || Loc == LastStateChangePos) {
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index cbf6cd0c5c..3aeaf19cd5 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -3109,6 +3109,10 @@ void ASTReader::ReadPragmaDiagnosticMappings(DiagnosticsEngine &Diag) {
     unsigned Idx = 0;
     while (Idx < F.PragmaDiagMappings.size()) {
       SourceLocation Loc = ReadSourceLocation(F, F.PragmaDiagMappings[Idx++]);
+      Diag.DiagStates.push_back(*Diag.GetCurDiagState());
+      Diag.DiagStatePoints.push_back(
+          DiagnosticsEngine::DiagStatePoint(&Diag.DiagStates.back(),
+                                            FullSourceLoc(Loc, SourceMgr)));
       while (1) {
         assert(Idx < F.PragmaDiagMappings.size() &&
                "Invalid data, didn't find '-1' marking end of diag/map pairs");
@@ -3121,8 +3125,8 @@ void ASTReader::ReadPragmaDiagnosticMappings(DiagnosticsEngine &Diag) {
           break; // no more diag/map pairs for this location.
         }
         diag::Mapping Map = (diag::Mapping)F.PragmaDiagMappings[Idx++];
-        // The user bit gets set by WritePragmaDiagnosticMappings.
-        Diag.setDiagnosticMapping(DiagID, Map, Loc);
+        DiagnosticMappingInfo MappingInfo = Diag.makeMappingInfo(Map, Loc);
+        Diag.GetCurDiagState()->setMappingInfo(DiagID, MappingInfo);
       }
     }
   }