From 12f37e411462b8388eb1309357bd62257debacac Mon Sep 17 00:00:00 2001
From: DeLesley Hutchins <delesley@google.com>
Date: Fri, 7 Dec 2012 22:53:48 +0000
Subject: [PATCH] Fix analysis based warnings so that all warnings are emitted
 when compiling with -Werror.  Previously, compiling with -Werror would emit
 only the first warning in a compilation unit, because clang assumes that once
 an error occurs, further analysis is unlikely to return valid results. 
 However, warnings that have been upgraded to errors should not be treated as
 "errors" in this sense.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169649 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Basic/Diagnostic.h   | 10 ++++++++++
 lib/Basic/Diagnostic.cpp           |  1 +
 lib/Basic/DiagnosticIDs.cpp        |  4 ++++
 lib/Sema/AnalysisBasedWarnings.cpp |  2 +-
 lib/Sema/SemaDecl.cpp              |  4 +++-
 5 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/include/clang/Basic/Diagnostic.h b/include/clang/Basic/Diagnostic.h
index 47a98bb462..5e9395cae0 100644
--- a/include/clang/Basic/Diagnostic.h
+++ b/include/clang/Basic/Diagnostic.h
@@ -279,6 +279,10 @@ private:
   /// \brief Sticky flag set to \c true when an error is emitted.
   bool ErrorOccurred;
 
+  /// \brief Sticky flag set to \c true when an "uncompilable error" occurs.
+  /// I.e. an error that was not upgraded from a warning by -Werror.
+  bool UncompilableErrorOccurred;
+
   /// \brief Sticky flag set to \c true when a fatal error is emitted.
   bool FatalErrorOccurred;
 
@@ -558,6 +562,12 @@ public:
                                   SourceLocation Loc = SourceLocation());
 
   bool hasErrorOccurred() const { return ErrorOccurred; }
+
+  /// \brief Errors that actually prevent compilation, not those that are
+  /// upgraded from a warning by -Werror.
+  bool hasUncompilableErrorOccurred() const {
+    return UncompilableErrorOccurred;
+  }
   bool hasFatalErrorOccurred() const { return FatalErrorOccurred; }
   
   /// \brief Determine whether any kind of unrecoverable error has occurred.
diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index 8346e39a67..f5eec02138 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -97,6 +97,7 @@ bool DiagnosticsEngine::popMappings(SourceLocation Loc) {
 
 void DiagnosticsEngine::Reset() {
   ErrorOccurred = false;
+  UncompilableErrorOccurred = false;
   FatalErrorOccurred = false;
   UnrecoverableErrorOccurred = false;
   
diff --git a/lib/Basic/DiagnosticIDs.cpp b/lib/Basic/DiagnosticIDs.cpp
index 722d22aa38..1237fd5db1 100644
--- a/lib/Basic/DiagnosticIDs.cpp
+++ b/lib/Basic/DiagnosticIDs.cpp
@@ -628,6 +628,10 @@ bool DiagnosticIDs::ProcessDiag(DiagnosticsEngine &Diag) const {
     if (isUnrecoverable(DiagID))
       Diag.UnrecoverableErrorOccurred = true;
 
+    // Warnings which have been upgraded to errors do not prevent compilation.
+    if (isDefaultMappingAsError(DiagID))
+      Diag.UncompilableErrorOccurred = true;
+
     Diag.ErrorOccurred = true;
     if (Diag.Client->IncludeInDiagnosticCounts()) {
       ++Diag.NumErrors;
diff --git a/lib/Sema/AnalysisBasedWarnings.cpp b/lib/Sema/AnalysisBasedWarnings.cpp
index 20f0fd8eef..0eca503cd5 100644
--- a/lib/Sema/AnalysisBasedWarnings.cpp
+++ b/lib/Sema/AnalysisBasedWarnings.cpp
@@ -1423,7 +1423,7 @@ AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
   if (cast<DeclContext>(D)->isDependentContext())
     return;
 
-  if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred()) {
+  if (Diags.hasUncompilableErrorOccurred() || Diags.hasFatalErrorOccurred()) {
     // Flush out any possibly unreachable diagnostics.
     flushDiagnostics(S, fscope);
     return;
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 9dd7779537..502a855728 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -8125,7 +8125,9 @@ Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
     if (PP.getDiagnostics().hasErrorOccurred() ||
         PP.getDiagnostics().getSuppressAllDiagnostics()) {
       DiscardCleanupsInEvaluationContext();
-    } else if (!isa<FunctionTemplateDecl>(dcl)) {
+    }
+    if (!PP.getDiagnostics().hasUncompilableErrorOccurred() &&
+        !isa<FunctionTemplateDecl>(dcl)) {
       // Since the body is valid, issue any analysis-based warnings that are
       // enabled.
       ActivePolicy = &WP;
-- 
2.40.0