Summary:
When using -ftrivial-auto-var-init=* options to initiate automatic
variables in a file, to disable initialization on some variables,
currently we have to manually annotate the variables with uninitialized
attribute, such as
int dont_initialize_me __attribute((uninitialized));
Making pragma clang attribute to support this attribute would make
annotating variables much easier, and could be particular useful for
bisection efforts, e.g.
void use(void*);
void buggy() {
int arr[256];
int boom;
float bam;
struct { int oops; } oops;
union { int oof; float aaaaa; } oof;
use(&arr);
use(&boom);
use(&bam);
use(&oops);
use(&oof);
}
Reviewers: jfb, rjmccall, aaron.ballman
Reviewed By: jfb, aaron.ballman
Subscribers: aaron.ballman, george.burgess.iv, dexonsmith, MaskRay, phosek, hubert.reinterpretcast, gbiv, manojgupta, llozano, srhines, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78693
Namespaces are introduced by adding an "identifier." before a
push/pop directive. Pop directives with namespaces can only pop a
attribute group that was pushed with the same namespace. Push and pop
directives that don't opt into namespaces have the same semantics.
This is necessary to prevent a pitfall of using multiple #pragma
clang attribute directives spread out in a large file, particularly
when macros are involved. It isn't easy to see which pop corripsonds
to which push, so its easy to inadvertently pop the wrong group.
Differential revision: https://reviews.llvm.org/D55628
llvm-svn: 349845
This reverts commit r345487, which reverted r345486. I think the crashes were
caused by an OOM on the builder, trying again to confirm...
llvm-svn: 345517
This commit enables pushing an empty #pragma clang attribute push, then adding
multiple attributes to it, then popping them all with #pragma clang attribute
pop, just like #pragma clang diagnostic. We still support the current way of
adding these, #pragma clang attribute push(__attribute__((...))), by treating it
like a combined push/attribute. This is needed to create macros like:
DO_SOMETHING_BEGIN(attr1, attr2, attr3)
// ...
DO_SOMETHING_END
rdar://45496947
Differential revision: https://reviews.llvm.org/D53621
llvm-svn: 345486
Summary:
We previously disallowed use of undocumented attributes with #pragma clang
attribute, but the justification for doing so was weak and it prevented many
reasonable use cases.
Reviewers: aaron.ballman, arphaman
Subscribers: cfe-commits, rnk, benlangmuir, dexonsmith, erik.pilkington
Differential Revision: https://reviews.llvm.org/D51507
llvm-svn: 341437
This is a recommit of r300539 that was reverted in r300543 due to test failures.
The original commit message is displayed below:
The new '#pragma clang attribute' directive can be used to apply attributes to
multiple declarations. An attribute must satisfy the following conditions to
be supported by the pragma:
- It must have a subject list that's defined in the TableGen file.
- It must be documented.
- It must not be late parsed.
- It must have a GNU/C++11 spelling.
Differential Revision: https://reviews.llvm.org/D30009
llvm-svn: 300556
The new '#pragma clang attribute' directive can be used to apply attributes to
multiple declarations. An attribute must satisfy the following conditions to
be supported by the pragma:
- It must have a subject list that's defined in the TableGen file.
- It must be documented.
- It must not be late parsed.
- It must have a GNU/C++11 spelling.
Differential Revision: https://reviews.llvm.org/D30009
llvm-svn: 300539
Jian Cai