[modules] Round-trip -Werror flag through explicit module build.

The intent for an explicit module build is that the diagnostics produced within
the module are those that were configured when the module was built, not those
that are enabled within a user of the module. This includes diagnostics that
don't actually show up until the module is used (for instance, diagnostics
produced during template instantiation and weird cases like -Wpadded).

We serialized and restored the diagnostic state for individual warning groups,
but previously did not track the state for flags like -Werror and -Weverything,
which are implemented as separate bits rather than as part of the diagnostics
mapping information.

llvm-svn: 301992

1 files changed, 3 insertions, 9 deletions

diff --git a/clang/lib/Basic/Diagnostic.cpp b/clang/lib/Basic/Diagnostic.cpp
index 350d5477751..6bdef78c074 100644
--- a/clang/lib/Basic/Diagnostic.cpp
+++ b/clang/lib/Basic/Diagnostic.cpp
@@ -67,18 +67,12 @@ DiagnosticsEngine::DiagnosticsEngine(IntrusiveRefCntPtr<DiagnosticIDs> diags,
   ArgToStringCookie = nullptr;
 
   AllExtensionsSilenced = 0;
-  IgnoreAllWarnings = false;
-  WarningsAsErrors = false;
-  EnableAllWarnings = false;
-  ErrorsAsFatal = false;
-  FatalsAsError = false;
-  SuppressSystemWarnings = false;
+  SuppressAfterFatalError = true;
   SuppressAllDiagnostics = false;
   ElideType = true;
   PrintTemplateTree = false;
   ShowColors = false;
   ShowOverloads = Ovl_All;
-  ExtBehavior = diag::Severity::Ignored;
 
   ErrorLimit = 0;
   TemplateBacktraceLimit = 0;
@@ -343,8 +337,8 @@ bool DiagnosticsEngine::setDiagnosticGroupErrorAsFatal(StringRef Group,
     return setSeverityForGroup(diag::Flavor::WarningOrError, Group,
                                diag::Severity::Fatal);
 
-  // Otherwise, we want to set the diagnostic mapping's "no Werror" bit, and
-  // potentially downgrade anything already mapped to be an error.
+  // Otherwise, we want to set the diagnostic mapping's "no Wfatal-errors" bit,
+  // and potentially downgrade anything already mapped to be a fatal error.
 
   // Get the diagnostics in this group.
   SmallVector<diag::kind, 8> GroupDiags;