Improvements to vexing-parse warnings. Make the no-parameters case more
accurate by asking the parser whether there was an ambiguity rather than trying
to reverse-engineer it from the DeclSpec. Make the with-parameters case have
better diagnostics by using semantic information to drive the warning,
improving the diagnostics and adding a fixit.
Patch by Nikola Smiljanic. Some minor changes by me to suppress diagnostics for
declarations of the form 'T (*x)(...)', which seem to have a very high false
positive rate, and to reduce indentation in 'warnAboutAmbiguousFunction'.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160998 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseTentative.cpp b/lib/Parse/ParseTentative.cpp
index 8cf1c29..1a4df47 100644
--- a/lib/Parse/ParseTentative.cpp
+++ b/lib/Parse/ParseTentative.cpp
@@ -671,7 +671,7 @@
// initializer that follows the declarator. Note that ctor-style
// initializers are not possible in contexts where abstract declarators
// are allowed.
- if (!mayBeAbstract && !isCXXFunctionDeclarator(false/*warnIfAmbiguous*/))
+ if (!mayBeAbstract && !isCXXFunctionDeclarator())
break;
// direct-declarator '(' parameter-declaration-clause ')'
@@ -1267,7 +1267,7 @@
/// '(' parameter-declaration-clause ')' cv-qualifier-seq[opt]
/// exception-specification[opt]
///
-bool Parser::isCXXFunctionDeclarator(bool warnIfAmbiguous) {
+bool Parser::isCXXFunctionDeclarator(bool *IsAmbiguous) {
// C++ 8.2p1:
// The ambiguity arising from the similarity between a function-style cast and
@@ -1304,23 +1304,13 @@
}
}
- SourceLocation TPLoc = Tok.getLocation();
PA.Revert();
+ if (IsAmbiguous && TPR == TPResult::Ambiguous())
+ *IsAmbiguous = true;
+
// In case of an error, let the declaration parsing code handle it.
- if (TPR == TPResult::Error())
- return true;
-
- if (TPR == TPResult::Ambiguous()) {
- // Function declarator has precedence over constructor-style initializer.
- // Emit a warning just in case the author intended a variable definition.
- if (warnIfAmbiguous)
- Diag(Tok, diag::warn_parens_disambiguated_as_function_decl)
- << SourceRange(Tok.getLocation(), TPLoc);
- return true;
- }
-
- return TPR == TPResult::True();
+ return TPR != TPResult::False();
}
/// parameter-declaration-clause:
@@ -1344,7 +1334,7 @@
Parser::TryParseParameterDeclarationClause(bool *InvalidAsDeclaration) {
if (Tok.is(tok::r_paren))
- return TPResult::True();
+ return TPResult::Ambiguous();
// parameter-declaration-list[opt] '...'[opt]
// parameter-declaration-list ',' '...'