Commit Graph

16 Commits

Author SHA1 Message Date
Volodymyr Sapsai 17ebdb239f Reland "[CodeGen] Fix crash when a function taking transparent union is redeclared."
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.

Now the fix is in converting from ABIArgInfo type to VarDecl type and using
argument demotion when necessary.

Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.

rdar://problem/34949329

Reviewers: rjmccall, rafael

Reviewed By: rjmccall

Subscribers: aemerson, cfe-commits, kristof.beyls, ahatanak

Differential Revision: https://reviews.llvm.org/D41311

llvm-svn: 323156
2018-01-22 22:29:24 +00:00
Volodymyr Sapsai 22b00ec42e Revert "[CodeGen] Fix crash when a function taking transparent union is redeclared."
This reverts commit r321296. It caused performance regressions
FAIL: imp.execution_time
FAIL: 2007-01-04-KNR-Args.execution_time
FAIL: sse_expandfft.execution_time
FAIL: sse_stepfft.execution_time

llvm-svn: 321306
2017-12-21 20:52:59 +00:00
Volodymyr Sapsai 614f3702d9 [CodeGen] Fix crash when a function taking transparent union is redeclared.
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.

The fix is in checking for the trivial case if ABIArgInfo type matches with
parameter declaration type. It exposed inconsistency that we check
hasScalarEvaluationKind for different types in EmitParmDecl and
EmitFunctionProlog, and comment says they should match.

Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.

rdar://problem/34949329

Reviewers: rjmccall, rafael

Reviewed By: rjmccall

Subscribers: aemerson, cfe-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D41311

llvm-svn: 321296
2017-12-21 19:42:37 +00:00
Volodymyr Sapsai 30680e9437 [Sema] Add support for flexible array members in Obj-C.
Allow Obj-C ivars with incomplete array type but only as the last ivar.
Also add a requirement for ivars that contain a flexible array member to
be at the end of class too. It is possible to add in a subclass another
ivar at the end but we'll emit a warning in this case. Also we'll emit a
warning if a variable sized ivar is declared in class extension or in
implementation because subclasses won't know they should avoid adding
new ivars.

In ARC incomplete array objects are treated as __unsafe_unretained so
require them to be marked as such.

Prohibit synthesizing ivars with flexible array members because order of
synthesized ivars is not obvious and tricky to control. Spelling out
ivar explicitly gives control to developers and helps to avoid surprises
with unexpected ivar ordering.

For C and C++ changed diagnostic to tell explicitly a field is not the
last one and point to the next field. It is not as useful as in Obj-C
but it is an improvement and it is consistent with Obj-C. For C for
unions emit more specific err_flexible_array_union instead of generic
err_field_incomplete.

rdar://problem/21054495

Reviewers: rjmccall, theraven

Reviewed By: rjmccall

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D38773

llvm-svn: 316381
2017-10-23 22:01:41 +00:00
Erich Keane 2fe684bb14 Allow attributes before union definition
permits typedef union __attribute__((transparent_union)) {...}

Differential Revision: https://reviews.llvm.org/D28266

llvm-svn: 296518
2017-02-28 20:44:39 +00:00
Alex Lorenz 6f4bc4f68d [Sema] Fix PR30520: Handle incomplete field types in transparent_union unions
This commit fixes a crash that happens when clang is analyzing a
transparent_union attribute on a union which has a field with incomplete type.

rdar://28630028

Differential Revision: https://reviews.llvm.org/D25273

llvm-svn: 283432
2016-10-06 09:47:29 +00:00
Benjamin Kramer 1adc8c3391 Print detailed vector type information on diagnostics.
We never aka vector types because our attributed syntax for it is less
comprehensible than the typedefs. This leaves the user in the dark when
the typedef isn't named that well.

Example:
  v2s v; v4f w;
  w = v;

The naming in this cases isn't even that bad, but the error we give is
useless without looking up the actual typedefs.
t.c:6:5: error: assigning to 'v4f' from incompatible type 'v2s'

Now:
t.c:6:5: error: assigning to 'v4f' (vector of 4 'float' values) from
    incompatible type 'v2s' (vector of 2 'int' values)

We do this for all diagnostics that print a vector type.

llvm-svn: 207267
2014-04-25 20:41:38 +00:00
Aaron Ballman 54fe5eb8cb Relaxing the alignment requirements for fields in a transparent_union. Emits the diagnostic only when subsequent alignments are more strict than the alignment required by the first field.
Fixes PR15134

llvm-svn: 200277
2014-01-28 01:47:34 +00:00
Alp Toker 11a71128b7 Forbid driver use in Sema tests
This ports the last Sema tests over to use the frontend directly, and adds a
local lit substitution to disable inappropriate %clang usage under this
directory.

llvm-svn: 199348
2014-01-16 02:37:08 +00:00
Peter Collingbourne 19b961d5f9 Merge transparent union types using member's unqualified type
llvm-svn: 120736
2010-12-02 21:00:06 +00:00
Peter Collingbourne 102ad54099 Merge transparent union types using member's canonical param type
llvm-svn: 120729
2010-12-02 20:02:29 +00:00
Peter Collingbourne a99fdcf93e Implement GNU C extension: two types are compatible if they appear
as a function argument, one of the types is a transparent union type
and the other type is compatible with a union member

llvm-svn: 117243
2010-10-24 18:30:18 +00:00
Douglas Gregor 2187266120 Complain about the application of a transparent_union attribute to a
union whose first field has integral vector type. Also, clean up this
diagnostic a bit. Thanks to Eli for spotting this change in semantics
last week.

llvm-svn: 107296
2010-06-30 17:24:13 +00:00
Douglas Gregor 4f4946aaaa Whenever we complain about a failed initialization of a function or
method parameter, provide a note pointing at the parameter itself so
the user does not have to manually look for the function/method being
called and match up parameters to arguments. For example, we now get:

t.c:4:5: warning: incompatible pointer types passing 'long *' to
parameter of
      type 'int *' [-pedantic]
  f(long_ptr);
    ^~~~~~~~
t.c:1:13: note: passing argument to parameter 'x' here
void f(int *x);
            ^

llvm-svn: 102038
2010-04-22 00:20:18 +00:00
Daniel Dunbar 5618e98f33 Update tests to use %clang instead of 'clang', and forcibly disable use of '
clang ' or ' clang -cc1 ' or ' clang-cc ' in test lines (by substituting them to
garbage).

llvm-svn: 91460
2009-12-15 22:01:24 +00:00
Douglas Gregor 0cfbdab0cf Implement semantic analysis for transparent unions. This is largely
based on a patch from Anders Johnsen. CodeGen support is incomplete,
in that we do not properly coerce to the first field's type.

llvm-svn: 70419
2009-04-29 22:16:16 +00:00