Commit Graph

20 Commits

Author SHA1 Message Date
Eli Friedman c11535c248 Add a warning to diagnose statements in C++ like "*(volatile int*)x;". Conceptually, this is part of -Wunused-value, but I added a separate flag -Wunused-volatile-lvalue so it doesn't get turned off by accident with -Wno-unused-value. I also made a few minor improvements to existing unused value warnings in the process. <rdar://problem/11516811>.
llvm-svn: 157362
2012-05-24 00:47:05 +00:00
Chad Rosier 96c755d13c C++ 5.2.10p2 has a note that mentions that, subject to all other restrictions,
a cast to the same type is allowed so long as it does not cast away constness.

Fix for PR11747. Patch by Aaron Ballman. Reviewed by Eli.

llvm-svn: 149664
2012-02-03 02:54:37 +00:00
Chandler Carruth 0dc3f8db1a Fix a bug in -Wundefined-reinterpret-cast where we failed to look
through sugared types when testing for TagTypes. This was the actual
cause of the only false positive in Clang+LLVM.

Next evaluation will be over a much larger selection of code including
large amounts of open source code.

llvm-svn: 131957
2011-05-24 07:43:19 +00:00
Argyrios Kyrtzidis 69a2c924b9 Add a warning for when reinterpret_cast leads to undefined behavior, patch by Richard Trieu!
llvm-svn: 130703
2011-05-02 18:21:19 +00:00
Argyrios Kyrtzidis bf04231a72 Don't allow reinterpret_cast to reference of vector element and property expression. Thanks goes to Eli Friedman!
llvm-svn: 130036
2011-04-22 23:57:57 +00:00
Argyrios Kyrtzidis 47a1285a69 reinterpret_cast to reference of a bit-field is not allowed.
Fixes rdar://9202628 & http://llvm.org/PR9564.

llvm-svn: 130024
2011-04-22 22:31:13 +00:00
Douglas Gregor b472e93af7 Implement appropriate semantics for C++ casting and conversion when
dealing with address-space- and GC-qualified pointers. Previously,
these qualifiers were being treated just like cvr-qualifiers (in some
cases) or were completely ignored, leading to uneven behavior. For
example, const_cast would allow conversion between pointers to
different address spaces.

The new semantics are fairly simple: reinterpret_cast can be used to
explicitly cast between pointers to different address spaces
(including adding/removing addresss spaces), while
static_cast/dynamic_cast/const_cast do not tolerate any changes in the
address space. C-style casts can add/remove/change address spaces
through the reinterpret_cast mechanism. Other non-CVR qualifiers
(e.g., Objective-C GC qualifiers) work similarly.

As part of this change, I tweaked the "casts away constness"
diagnostic to use the term "casts away qualifiers". The term
"constness" actually comes from the C++ standard, despite the fact
that removing "volatile" also falls under that category. In Clang, we
also have restrict, address spaces, ObjC GC attributes, etc., so the
more general "qualifiers" is clearer.

llvm-svn: 129583
2011-04-15 17:59:54 +00:00
Daniel Dunbar 53c9ac30f9 tests: Use -ffreestanding when including stdint.h, to avoid platform dependencies.
llvm-svn: 113301
2010-09-07 22:54:28 +00:00
Chris Lattner 9dd55103c1 print "const intptr_t" instead of "intptr_t const"
llvm-svn: 113091
2010-09-05 00:07:29 +00:00
Chris Lattner 53fa04909c make clang print types as "const int *" instead of "int const*",
which is should have done from the beginning.  As usual, the most
fun with this sort of change is updating all the testcases.

llvm-svn: 113090
2010-09-05 00:04:01 +00:00
Anders Carlsson 76f513f862 When deciding whether reinterpret_cast casts away constness we need to look at array qualifiers. Fixes rdar://problem/8018292.
llvm-svn: 105494
2010-06-04 22:47:55 +00:00
John McCall 85f9055955 When pretty-printing tag types, only print the tag if we're in C (and
therefore not creating ElaboratedTypes, which are still pretty-printed
with the written tag).

Most of these testcase changes were done by script, so don't feel too
sorry for my fingers.

llvm-svn: 98149
2010-03-10 11:27:22 +00:00
Douglas Gregor b92a1565c3 Implement the lvalue-to-rvalue conversion where needed. The
lvalue-to-rvalue conversion adjusts lvalues of qualified, non-class
type to rvalue expressions of the unqualified variant of that
type. For example, given:

  const int i;
  (void)(i + 17);

the lvalue-to-rvalue conversion for the subexpression "i" will turn it
from an lvalue expression (a DeclRefExpr) with type 'const int' into
an rvalue expression with type 'int'. Both C and C++ mandate this
conversion, and somehow we've slid through without implementing it. 

We now have both DefaultFunctionArrayConversion and
DefaultFunctionArrayLvalueConversion, and which gets used depends on
whether we do the lvalue-to-rvalue conversion or not. Generally, we do
the lvalue-to-rvalue conversion, but there are a few notable
exceptions:
  - the left-hand side of a '.' operator
  - the left-hand side of an assignment
  - a C++ throw expression
  - a subscript expression that's subscripting a vector

Making this change exposed two issues with blocks:
  - we were deducing const-qualified return types of non-class type
  from a block return, which doesn't fit well
  - we weren't always setting the known return type of a block when it
  was provided with the ^return-type syntax

Fixes the current Clang-on-Clang compile failure and PR6076.

llvm-svn: 95167
2010-02-03 00:27:59 +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
Alexis Hunt 12048d868b Use intptr_t rather than long so that this test will not fail on LLP64 systems,
where long is only 32-bits and so a reinterpret_cast would be ill-formed.

llvm-svn: 89583
2009-11-22 07:05:50 +00:00
Sebastian Redl 55db1ec3ec CastsAwayConstness shouldn't care if member pointers point into different classes. Fixes PR5545.
llvm-svn: 89215
2009-11-18 18:10:53 +00:00
Argyrios Kyrtzidis b1d51aa18a Use "()" instead of "(void)" when pretty-printing a parameter-less function type for C++.
llvm-svn: 72747
2009-06-03 02:06:50 +00:00
Daniel Dunbar a45cf5b6b0 Rename clang to clang-cc.
Tests and drivers updated, still need to shuffle dirs.

llvm-svn: 67602
2009-03-24 02:24:46 +00:00
Sebastian Redl a5a77a6dc6 Add handling of member pointers to reinterpret_cast.
llvm-svn: 63150
2009-01-27 23:18:31 +00:00
Douglas Gregor 08d918a6c3 Semantic analysis for C++ reinterpret_cast and const_cast. Patch by Sebastian Redl.
llvm-svn: 58094
2008-10-24 15:36:09 +00:00