Commit Graph

7 Commits

Author SHA1 Message Date
Tomas Matheson 7e5cea5b50 [Clang][Sema] Warn when function argument is less aligned than parameter
See https://bugs.llvm.org/show_bug.cgi?id=42154.

GCC's __attribute__((align)) can reduce the alignment of a type when applied to
a typedef.  However, functions which take a pointer or reference to the
original type are compiled assuming the original alignment.  Therefore when any
such function is passed an object of the new, less-aligned type, an alignment
fault can occur.  In particular, this applies to the constructor, which is
defined for the original type and called for the less-aligned object.

This change adds a warning whenever an pointer or reference to an object is
passed to a function that was defined for a more-aligned type.

The calls to ASTContext::getTypeAlignInChars seem change the order in which
record layouts are evaluated, which caused changes to the output of
-fdump-record-layouts. As such some tests needed to be updated:

  * Use CHECK-LABEL rather than counting the number of "Dumping AST Record
    Layout" headers.

  * Check for end of line in labels, so that struct B1 doesn't match struct B
    etc.

  * Add --strict-whitespace, since the whitespace shows meaningful structure.

  * The order in which record layouts are printed has changed in some cases.

  * clang-format for regions changed

Differential Revision: https://reviews.llvm.org/D97187
2021-03-09 10:37:32 +00:00
Aaron Ballman 674cf26892 __declspec is not a core Clang language extension. Instead, require -fms-extensions or -fborland to enable the language extension.
Note: __declspec is also temporarily enabled when compiling for a CUDA target because there are implementation details relying on __declspec(property) support currently. When those details change, __declspec should be disabled for CUDA targets.
llvm-svn: 238238
2015-05-26 19:44:52 +00:00
Warren Hunt c89450e054 [MS-ABI] Drop Special Layout in 64-bit mode.
As of cl.exe version 18, the special layout rules for structs with 
alignment 16 or greater has been dropped.  This patch drops the behavior 
from clang.  This patch also updates the lit tests to reflect the 
change.

llvm-svn: 204674
2014-03-24 21:37:27 +00:00
Hans Wennborg c9bd88e681 Remove the -cxx-abi command-line flag.
This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250
2014-01-14 19:35:09 +00:00
Warren Hunt d640d7d96e [ms-abi] Refactor Microsoft Record Layout
This patch refactors microsoft record layout to be more "natural".  The 
most dominant change is that vbptrs and vfptrs are injected after the 
fact.  This simplifies the implementation and the math for the offest 
for the first base/field after the vbptr.

llvm-svn: 198818
2014-01-09 00:30:56 +00:00
Warren Hunt 55d8e82f86 Implements 64 bit microsoft record layout and adds lit tests to cover
it.  Also removes all of the microsoft C++ ABI related code from the 
itanium layout builder.

Differential Revision: http://llvm-reviews.chandlerc.com/D2003

llvm-svn: 193290
2013-10-23 23:53:07 +00:00
Warren Hunt bd1b0c6916 Lit tests for Microsoft C++ record layout.
They weren't added with the rest of the microsoft record layout patch due me not 
doing svn add.

llvm-svn: 192612
2013-10-14 19:08:58 +00:00