Implement support for the extremely atrocious MS /##/ extension,
which pastes together a comment. This is only enabled with
-fms-extensions of course.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@46845 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Lex/MacroExpander.cpp b/Lex/MacroExpander.cpp
index 9d4b072..4e62c94 100644
--- a/Lex/MacroExpander.cpp
+++ b/Lex/MacroExpander.cpp
@@ -508,7 +508,11 @@
// If this token is followed by a token paste (##) operator, paste the tokens!
if (!isAtEnd() && MacroTokens[CurToken].is(tok::hashhash))
- PasteTokens(Tok);
+ if (PasteTokens(Tok)) {
+ // When handling the microsoft /##/ extension, the final token is
+ // returned by PasteTokens, not the pasted token.
+ return;
+ }
// The token's current location indicate where the token was lexed from. We
// need this information to compute the spelling of the token, but any
@@ -538,7 +542,8 @@
/// PasteTokens - Tok is the LHS of a ## operator, and CurToken is the ##
/// operator. Read the ## and RHS, and paste the LHS/RHS together. If there
/// are is another ## after it, chomp it iteratively. Return the result as Tok.
-void MacroExpander::PasteTokens(Token &Tok) {
+/// If this returns true, the caller should immediately return the token.
+bool MacroExpander::PasteTokens(Token &Tok) {
llvm::SmallVector<char, 128> Buffer;
do {
// Consume the ## operator.
@@ -621,10 +626,18 @@
// This occurs with "x ## +" and other stuff. Return with Tok unmodified
// and with RHS as the next token to lex.
if (isInvalid) {
- // If not in assembler language mode.
- PP.Diag(PasteOpLoc, diag::err_pp_bad_paste,
- std::string(Buffer.begin(), Buffer.end()-1));
- return;
+ // Test for the Microsoft extension of /##/ turning into // here on the
+ // error path.
+ if (PP.getLangOptions().Microsoft && Tok.is(tok::slash) &&
+ RHS.is(tok::slash)) {
+ HandleMicrosoftCommentPaste(Tok);
+ return true;
+ } else {
+ // TODO: If not in assembler language mode.
+ PP.Diag(PasteOpLoc, diag::err_pp_bad_paste,
+ std::string(Buffer.begin(), Buffer.end()-1));
+ return false;
+ }
}
// Turn ## into 'other' to avoid # ## # from looking like a paste operator.
@@ -649,6 +662,7 @@
// by saying we're skipping contents, so we need to do this manually.
Tok.setIdentifierInfo(PP.LookUpIdentifierInfo(Tok));
}
+ return false;
}
/// isNextTokenLParen - If the next token lexed will pop this macro off the
@@ -660,3 +674,21 @@
return 2;
return MacroTokens[CurToken].is(tok::l_paren);
}
+
+
+/// HandleMicrosoftCommentPaste - In microsoft compatibility mode, /##/ pastes
+/// together to form a comment that comments out everything in the current
+/// macro, other active macros, and anything left on the current physical
+/// source line of the instantiated buffer. Handle this by returning the
+/// first token on the next line.
+void MacroExpander::HandleMicrosoftCommentPaste(Token &Tok) {
+ // We 'comment out' the rest of this macro by just ignoring the rest of the
+ // tokens that have not been lexed yet, if any.
+
+ // Since this must be a macro, mark the macro enabled now that it is no longer
+ // being expanded.
+ assert(Macro && "Token streams can't paste comments");
+ Macro->EnableMacro();
+
+ PP.HandleMicrosoftCommentPaste(Tok);
+}