Commit Graph

9 Commits

Author SHA1 Message Date
Richard Smith 541b38be7b Switch the semantic DeclContext for a block-scope declaration of a function or
variable from being the function to being the enclosing namespace scope (in
C++) or the TU (in C). This allows us to fix a selection of related issues
where we would build incorrect redeclaration chains for such declarations, and
fail to notice type mismatches.

Such declarations are put into a new IdentifierNamespace, IDNS_LocalExtern,
which is only found when searching scopes, and not found when searching
DeclContexts. Such a declaration is only made visible in its DeclContext if
there are no non-LocalExtern declarations.

llvm-svn: 191064
2013-09-20 01:15:31 +00:00
Richard Smith 1c34fb78e7 Fix implementation of C11 6.2.7/4 and C++11 [dcl.array]p3:
When a local extern declaration redeclares some other entity, the type of that
entity is merged with the prior type if the prior declaration is visible (in C)
or is declared in the same scope (in C++).

 - Make LookupRedeclarationWithLinkage actually work in C++, use it in the right
   set of cases, and make it track whether it found a shadowed declaration.
 - Track whether we found a declaration in the same scope (for C++) including
   across serialization and template instantiation.

llvm-svn: 188307
2013-08-13 18:18:50 +00:00
John McCall b65e8fe143 Only merge down a variable type if the previous declaration was
visible.  There's a lot of potential badness in how we're modelling
these things, but getting this much correct is reasonably easy.

rdar://13535367

llvm-svn: 178488
2013-04-01 18:34:28 +00:00
Richard Smith 8d06f42448 Improve 0-argument -Wvexing-parse diagnostic by adding notes with fix-its:
- If the declarator is at the start of a line, and the previous line contained
   another declarator and ended with a comma, then that comma was probably a
   typo for a semicolon:

   int n = 0, m = 1, l = 2, // k = 5;
   myImportantFunctionCall(); // oops!

 - If removing the parentheses would correctly initialize the object, then
   produce a note suggesting that fix.

 - Otherwise, if there is a simple initializer we can suggest which performs
   value-initialization, then provide a note suggesting a correction to that
   initializer.

Sema::Declarator now tracks the location of the comma prior to the declarator in
the declaration, if there is one, to facilitate providing the note. The code to
determine an appropriate initializer from the -Wuninitialized warning has been
factored out to allow use in both that and -Wvexing-parse.

llvm-svn: 148072
2012-01-12 23:53:29 +00:00
Richard Smith b3851f5ca1 David Blaikie and Chandler would like us to diagnose
int f();

in function scopes under -Wvexing-parse, so now we do.

llvm-svn: 147649
2012-01-06 02:30:50 +00:00
Richard Smith d069d2f6ac Tweak to r147599 for PR10828: Move the check from the parser into sema, and use
the Semantic Powers to only warn on class types (or dependent types), where the
constructor or destructor could do something interesting.

llvm-svn: 147642
2012-01-06 01:31:20 +00:00
Richard Smith 69f90dce49 PR10828: Produce a warning when a no-arguments function is declared in block
scope, when no other indication is provided that the user intended to declare a
function rather than a variable.

Remove some false positives from the existing 'parentheses disambiguated as a
function' warning by suppressing it when the declaration is marked as 'typedef'
or 'extern'.

Add a new warning group -Wvexing-parse containing both of these warnings.

The new warning is enabled by default; despite a number of false positives (and
one bug) in clang's test-suite, I have only found genuine bugs with it when
running it over a significant quantity of real C++ code.

llvm-svn: 147599
2012-01-05 04:12:21 +00:00
Daniel Dunbar 8fbe78f6fc Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
- This is designed to make it obvious that %clang_cc1 is a "test variable"
   which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
   can be useful to redefine what gets run as 'clang -cc1' (for example, to set
   a default target).

llvm-svn: 91446
2009-12-15 20:14:24 +00:00
Douglas Gregor f73b282bf0 Implement the rules in C++ [basic.link] and C99 6.2.2 for computing
the linkage of a declaration. Switch the lame (and completely wrong)
NamedDecl::hasLinkage() over to using the new NamedDecl::getLinkage(),
along with the "can this declaration be a template argument?" check
that started all of this.

Fixes -fsyntax-only for PR5597.

llvm-svn: 89891
2009-11-25 22:24:25 +00:00