Commit Graph

6 Commits

Author SHA1 Message Date
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Erik Pilkington 02d5fb1a6e Add a spelling of pass_object_size that uses __builtin_dynamic_object_size
The attribute pass_dynamic_object_size(n) behaves exactly like
pass_object_size(n), but instead of evaluating __builtin_object_size on calls,
it evaluates __builtin_dynamic_object_size, which has the potential to produce
runtime code when the object size can't be determined statically.

Differential revision: https://reviews.llvm.org/D58757

llvm-svn: 356515
2019-03-19 20:44:18 +00:00
George Burgess IV 2099b54102 [Sema] Relax overloading restrictions in C.
This patch allows us to perform incompatible pointer conversions when
resolving overloads in C. So, the following code will no longer fail to
compile (though it will still emit warnings, assuming the user hasn't
opted out of them):

```
void foo(char *) __attribute__((overloadable));
void foo(int) __attribute__((overloadable));

void callFoo() {
  unsigned char bar[128];
  foo(bar); // selects the char* overload.
}
```

These conversions are ranked below all others, so:

  A. Any other viable conversion will win out
  B. If we had another incompatible pointer conversion in the example
     above (e.g. `void foo(int *)`), we would complain about
     an ambiguity.

Differential Revision: https://reviews.llvm.org/D24113

llvm-svn: 280553
2016-09-02 22:59:57 +00:00
George Burgess IV 6da4c20f7d [Sema] Allow implicit conversions of &overloaded_fn in C.
Also includes a minor ``enable_if`` docs update.

Currently, our address-of overload machinery will only allow implicit
conversions of overloaded functions to void* in C. For example:

```
void f(int) __attribute__((overloadable));
void f(double) __attribute__((overloadable, enable_if(0, "")));

void *fp = f; // OK. This is C and the target is void*.
void (*fp2)(void) = f; // Error. This is C, but the target isn't void*.
```

This patch makes the assignment of `fp2` select the `f(int)` overload,
rather than emitting an error (N.B. you'll still get a warning about the
`fp2` assignment if you use -Wincompatible-pointer-types).

Differential Revision: http://reviews.llvm.org/D13704

llvm-svn: 264132
2016-03-23 02:33:58 +00:00
George Burgess IV 7204ed97dd [Sema] Teach overload resolution about unaddressable functions.
Given an expression like `(&Foo)();`, we perform overload resolution as
if we are calling `Foo` directly. This causes problems if `Foo` is a
function that can't have its address taken. This patch teaches overload
resolution to ignore functions that can't have their address taken in
such cases.

Differential Revision: http://reviews.llvm.org/D15590

llvm-svn: 257016
2016-01-07 02:26:57 +00:00
George Burgess IV 08a4a8c389 Add tests for pass_object_size.
These additions were meant to go in as a part of r254554; while it's
certainly nice to have new functionality, it's nicer if we have tests to
go with it. :)

llvm-svn: 254632
2015-12-03 19:19:09 +00:00