[libclang] Allow skipping warnings from all included files

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 * https://reviews.llvm.org/D48116
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Depending on the included files and the used warning flags, e.g. -
Weverything, a huge number of warnings can be reported for included
files. As processing that many diagnostics comes with a performance
impact and not all clients are interested in those diagnostics, add a
flag to skip them.

Change-Id: Ia738a9382b43d210046bff68b3be8cb9dd89206f
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

2 files changed, 9 insertions, 0 deletions

diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index 26baa838f8..dd15c83e5b 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -70,6 +70,7 @@ DiagnosticsEngine::DiagnosticsEngine(IntrusiveRefCntPtr<DiagnosticIDs> diags,
   AllExtensionsSilenced = 0;
   SuppressAfterFatalError = true;
   SuppressAllDiagnostics = false;
+  SuppressNonErrorsFromIncludedFiles = false;
   ElideType = true;
   PrintTemplateTree = false;
   ShowColors = false;
diff --git a/lib/Basic/DiagnosticIDs.cpp b/lib/Basic/DiagnosticIDs.cpp
index c4c425d9eb..ab7802651d 100644
--- a/lib/Basic/DiagnosticIDs.cpp
+++ b/lib/Basic/DiagnosticIDs.cpp
@@ -477,6 +477,14 @@ DiagnosticIDs::getDiagnosticSeverity(unsigned DiagID, SourceLocation Loc,
       Result = diag::Severity::Fatal;
   }
 
+  // If requested, ignore warnings from all headers.
+  if (Diag.SuppressNonErrorsFromIncludedFiles &&
+      Result <= diag::Severity::Warning && Loc.isValid() &&
+      !Diag.getSourceManager().isInMainFile(
+          Diag.getSourceManager().getExpansionLoc(Loc))) {
+    return diag::Severity::Ignored;
+  }
+
   // Custom diagnostics always are emitted in system headers.
   bool ShowInSystemHeader =
       !GetDiagInfo(DiagID) || GetDiagInfo(DiagID)->WarnShowInSystemHeader;