[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |8.5
           Priority|P3                          |P4

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Reduced testcase:
void bar ();

void
foo (char a)
{
  union C { int d[100.0]; char *e; };
  bar ((union C) &a);
}

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P4                          |P2

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 48135
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48135&action=edit
gcc10-pr93573.patch

For the error-recovery ICE, we can just make sure that after errors the type
isn't assumed to be VLA.

Unfortunately:
void bar ();

void
foo (char a, int b)
{
  union C { int d[b]; char *e; };
  bar ((union C) &a);
}

still ICEs.

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:c6a562de88c44a555e1688c212869b20b02151bc

commit r10-7438-gc6a562de88c44a555e1688c212869b20b02151bc
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Mar 28 10:30:31 2020 +0100

    c: After issuing errors about array size, for error-recovery don't make the
array VLA [PR93573]

    After we report various errors about array size, we set for error-recovery
    the size to be 1, but because size_int_const is false, it still means we
    pretend the array is a VLA, can emit a second diagnostics in that case etc.
    E.g.
    $ ./cc1.unpatched -quiet a.c
    a.c:1:5: error: size of array âfâ has non-integer type
        1 | int f[100.0];
          |     ^
    a.c:1:1: warning: variably modified âfâ at file scope
        1 | int f[100.0];
          | ^~~
    $ ./cc1 -quiet a.c
    a.c:1:5: error: size of array âfâ has non-integer type
        1 | int f[100.0];
          |     ^

    2020-03-28  Jakub Jelinek  <jakub@redhat.com>

            PR c/93573
            * c-decl.c (grokdeclarator): After issuing errors, set
size_int_const
            to true after setting size to integer_one_node.

            * gcc.dg/pr93573-1.c: New test.
            * gcc.dg/pr93573-2.c: New test.

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed the error-recovery bug on the trunk, but the ice on the #c4 testcase is
still there (and the question is if it is valid or not).  If it is valid,
probably the FE or gimplifier needs to turn that cast to VLA union into
creation of a VLA temporary and assigning the cast operand into the right field
of it.

[Bug c/93573] [8/9/10 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #7 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
Passing a variable-size struct or union by value to a non-nested function 
seems very questionable (the function couldn't be declared with a matching 
prototype), but perhaps that doesn't answer the question because the 
cast-to-union case might appear for a nested function as well.

[Bug c/93573] [9/10/11/12 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|8.5                         |9.4

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 8 branch is being closed.

[Bug c/93573] [9/10/11/12 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|9.4                         |9.5

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9.4 is being released, retargeting bugs to GCC 9.5.

[Bug c/93573] [10/11/12/13 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|9.5                         |10.4

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9 branch is being closed

[Bug c/93573] [10/11/12/13 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.4                        |10.5

--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 10.4 is being released, retargeting bugs to GCC 10.5.

[Bug c/93573] [11/12/13/14 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.5                        |11.5

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 10 branch is being closed.

[Bug c/93573] [11/12/13/14 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #13 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #6)
> Fixed the error-recovery bug on the trunk, but the ice on the #c4 testcase
> is still there (and the question is if it is valid or not).  If it is valid,
> probably the FE or gimplifier needs to turn that cast to VLA union into
> creation of a VLA temporary and assigning the cast operand into the right
> field of it.

Hmm, is the testcase in comment #4 a regression though? It ICEs even in the
same way in GCC 4.1.2 all the way to the trunk including GCC 7.3.0.

[Bug c/93573] [11/12/13/14 Regression] internal compiler error: in force_constant_size, at gimplify.c:733

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93573

--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #13)
> Hmm, is the testcase in comment #4 a regression though? It ICEs even in the
> same way in GCC 4.1.2 all the way to the trunk including GCC 7.3.0.

It is.  gcc 3.2, 3.3 and 3.4 at least compile that just fine,
while r0-63127-ga63c0d13291b93a42e927d0356b2d9854c654337 ICEs.