Parse and ignore #pragma runtime_checks in MS extensions mode (PR25138)

We already silently ignore the /RTC, which controls the same functionality.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@250099 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Lex/Pragma.h

@@ -76,7 +76,7 @@ public:
 /// used to ignore particular pragmas.
 class EmptyPragmaHandler : public PragmaHandler {
 public:
-  EmptyPragmaHandler();
+  explicit EmptyPragmaHandler(StringRef Name = StringRef());
 
   void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
                     Token &FirstToken) override;

include/clang/Parse/Parser.h

@@ -163,6 +163,7 @@ class Parser : public CodeCompletionHandler {
   std::unique_ptr<PragmaHandler> MSConstSeg;
   std::unique_ptr<PragmaHandler> MSCodeSeg;
   std::unique_ptr<PragmaHandler> MSSection;
+  std::unique_ptr<PragmaHandler> MSRuntimeChecks;
   std::unique_ptr<PragmaHandler> OptimizeHandler;
   std::unique_ptr<PragmaHandler> LoopHintHandler;
   std::unique_ptr<PragmaHandler> UnrollHintHandler;

lib/Lex/Pragma.cpp

@@ -38,7 +38,7 @@ PragmaHandler::~PragmaHandler() {
 // EmptyPragmaHandler Implementation.
 //===----------------------------------------------------------------------===//
 
-EmptyPragmaHandler::EmptyPragmaHandler() {}
+EmptyPragmaHandler::EmptyPragmaHandler(StringRef Name) : PragmaHandler(Name) {}
 
 void EmptyPragmaHandler::HandlePragma(Preprocessor &PP, 
                                       PragmaIntroducerKind Introducer,

lib/Parse/ParsePragma.cpp

@@ -156,6 +156,10 @@ struct PragmaUnrollHintHandler : public PragmaHandler {
                     Token &FirstToken) override;
 };
 
+struct PragmaMSRuntimeChecksHandler : public EmptyPragmaHandler {
+  PragmaMSRuntimeChecksHandler() : EmptyPragmaHandler("runtime_checks") {}
+};
+
 }  // end namespace
 
 void Parser::initializePragmaHandlers() {
@@ -222,6 +226,8 @@ void Parser::initializePragmaHandlers() {
     PP.AddPragmaHandler(MSCodeSeg.get());
     MSSection.reset(new PragmaMSPragma("section"));
     PP.AddPragmaHandler(MSSection.get());
+    MSRuntimeChecks.reset(new PragmaMSRuntimeChecksHandler());
+    PP.AddPragmaHandler(MSRuntimeChecks.get());
   }
 
   OptimizeHandler.reset(new PragmaOptimizeHandler(Actions));
@@ -288,6 +294,8 @@ void Parser::resetPragmaHandlers() {
     MSCodeSeg.reset();
     PP.RemovePragmaHandler(MSSection.get());
     MSSection.reset();
+    PP.RemovePragmaHandler(MSRuntimeChecks.get());
+    MSRuntimeChecks.reset();
   }
 
   PP.RemovePragmaHandler("STDC", FPContractHandler.get());

test/Preprocessor/pragma_microsoft.c

-// RUN: %clang_cc1 %s -fsyntax-only -verify -fms-extensions
+// RUN: %clang_cc1 %s -fsyntax-only -verify -fms-extensions -Wunknown-pragmas
 // RUN: not %clang_cc1 %s -fms-extensions -E | FileCheck %s
 // REQUIRES: non-ps4-sdk
 
@@ -53,7 +53,7 @@ __pragma(comment(linker," bar=" BAR))
 
 void f()
 {
-  __pragma()
+  __pragma() // expected-warning{{unknown pragma ignored}}
 // CHECK: #pragma
 
   // If we ever actually *support* __pragma(warning(disable: x)),
@@ -159,3 +159,6 @@ void g() {}
 #pragma warning(default 321) // expected-warning {{expected ':'}}
 #pragma warning(asdf : 321) // expected-warning {{expected 'push', 'pop'}}
 #pragma warning(push, -1) // expected-warning {{requires a level between 0 and 4}}
+
+// Test that runtime_checks is parsed but ignored.
+#pragma runtime_checks("sc", restore) // no-warning