[c++20] Implement tweaked __VA_OPT__ rules from P1042R1:
* __VA_OPT__ is expanded if the *expanded* __VA_ARGS__ is non-empty,
not if the original argument contained no tokens.
* Placemarkers at the start and end of __VA_OPT__ are retained just
long enough to paste them with adjacent ## operators. We never paste
"across" a discarded placemarker.
llvm-svn: 359964
diff --git a/clang/lib/Lex/MacroArgs.cpp b/clang/lib/Lex/MacroArgs.cpp
index dd0b79c..06e3add 100644
--- a/clang/lib/Lex/MacroArgs.cpp
+++ b/clang/lib/Lex/MacroArgs.cpp
@@ -135,15 +135,12 @@
return Result;
}
-// This function assumes that the variadic arguments are the tokens
-// corresponding to the last parameter (ellipsis) - and since tokens are
-// separated by the 'eof' token, if that is the only token corresponding to that
-// last parameter, we know no variadic arguments were supplied.
-bool MacroArgs::invokedWithVariadicArgument(const MacroInfo *const MI) const {
+bool MacroArgs::invokedWithVariadicArgument(const MacroInfo *const MI,
+ Preprocessor &PP) {
if (!MI->isVariadic())
return false;
const int VariadicArgIndex = getNumMacroArguments() - 1;
- return getUnexpArgument(VariadicArgIndex)->isNot(tok::eof);
+ return getPreExpArgument(VariadicArgIndex, PP).front().isNot(tok::eof);
}
/// ArgNeedsPreexpansion - If we can prove that the argument won't be affected