Forward #pragma comment(lib/linker) through as flags metadata

Summary:
Most of this change is wiring the pragma all the way through from the
lexer, parser, and sema to codegen.  I considered adding a Decl AST node
for this, but it seemed too heavyweight.

Mach-O already uses a metadata flag called "Linker Options" to do this
kind of auto-linking.  This change follows that pattern.

LLVM knows how to forward the "Linker Options" metadata into the COFF
.drectve section where these flags belong.  ELF support is not
implemented, but possible.

This is related to auto-linking, which is http://llvm.org/PR13016.

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D723

llvm-svn: 181426

1 files changed, 21 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index e12bbde0d0d..bc19b382989 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -13,6 +13,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Sema/SemaInternal.h"
+#include "clang/AST/ASTConsumer.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Expr.h"
 #include "clang/Basic/TargetInfo.h"
@@ -263,6 +264,26 @@ void Sema::ActOnPragmaMSStruct(PragmaMSStructKind Kind) {
   MSStructPragmaOn = (Kind == PMSST_ON);
 }
 
+void Sema::ActOnPragmaMSComment(PragmaMSCommentKind Kind, llvm::StringRef Arg) {
+  // FIXME: Serialize this.
+  switch (Kind) {
+  case PCK_Unknown:
+    llvm_unreachable("unexpected pragma comment kind");
+  case PCK_Linker:
+    Consumer.HandleLinkerOptionPragma(Arg);
+    return;
+  case PCK_Lib: {
+    Consumer.HandleDependentLibrary(Arg);
+    return;
+  }
+  case PCK_Compiler:
+  case PCK_ExeStr:
+  case PCK_User:
+    return;  // We ignore all of these.
+  }
+  llvm_unreachable("invalid pragma comment kind");
+}
+
 void Sema::ActOnPragmaUnused(const Token &IdTok, Scope *curScope,
                              SourceLocation PragmaLoc) {