[Bug fortran/115528] New: [15 regression] segmentation fault in legacy F77 code

[Bug fortran/115528] New: [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

            Bug ID: 115528
           Summary: [15 regression] segmentation fault in legacy F77 code
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: juergen.reuter at desy dot de
  Target Milestone: ---

Some changes in gcc/gfortran between ca. June 10 and June 17, 2024 now leeds to
segmenation faults in our application (Whizard v3.1.4, c.f.
http://whizard.hepforge.org/whizard-3.1.4.tar.gz). Note that this appears in
our functional testsuite which necessitates the OCaml compiler. The
segmentation fault appears e.g. as 
#0  0x7f827594f51f in ???
        at ./signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
#1  0x7f827a3cfd0a in curr_
        at ../../../contrib/tauola/formf.f:599
#2  0x7f827a3e0e16 in dam4pi_
        at ../../../contrib/tauola/tauola.f:4106
#3  0x7f827a3e1fb6 in dph4pi_
        at ../../../contrib/tauola/tauola.f:4067
#4  0x7f827a3e6510 in dadnew_
        at ../../../contrib/tauola/tauola.f:3667
#5  0x7f827a3e685c in dexnew_
        at ../../../contrib/tauola/tauola.f:3592
#6  0x7f827a3ecc2d in dexay_
        at ../../../contrib/tauola/tauola.f:525
#7  0x7f827a3eeffa in initdk_
        at ../../../contrib/tauola/tauola_photos_ini.f:452

I need to come up with a workable reproducer, but that's not easy, and my time
nowadays is awfully limited. :(

[Bug fortran/115528] [15 regression] segmentation fault in legacy F77 code

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
   Target Milestone|---                         |15.0

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
what options are you using to compile the source?
Does it work at -O0?

[Bug fortran/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #2 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Andrew Pinski from comment #1)
> what options are you using to compile the source?
> Does it work at -O0?

You are right: the problem doesn't appear for -O0. Our defaults are the libtool
defaults of -g -O2.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |WAITING
           Keywords|                            |needs-bisection
   Last reconfirmed|                            |2024-06-18

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
We still need a testcase of some sort, or possibly bisection.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #4 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Created attachment 58462
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58462&action=edit
Input file that triggers the test case with segmentation fault

This test case needs Whizard 3.1.4 to be downloaded here,
http://whizard.hepforge.org/whizard-3.1.4.tar.gz
I avoided the need for OCaml being present, just do ./configure, make, make
install. This will create a binary whizard, and then execute
whizard tauola_1.sin as attached.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[kargls at comcast dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

kargls at comcast dot net changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |kargls at comcast dot net

--- Comment #5 from kargls at comcast dot net ---
(In reply to Jürgen Reuter from comment #4)
> Created attachment 58462 [details]
> Input file that triggers the test case with segmentation fault
> 
> This test case needs Whizard 3.1.4 to be downloaded here,
> http://whizard.hepforge.org/whizard-3.1.4.tar.gz
> I avoided the need for OCaml being present, just do ./configure, make, make
> install. This will create a binary whizard, and then execute
> whizard tauola_1.sin as attached.

./configure
...
checking for OCaml version 408000... test: -ge: unexpected operator
< 4.08.0
configure: error: *************************************
configure: error: found version , too old!
configure: error: *************************************

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #6 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to kargls from comment #5)
> (In reply to Jürgen Reuter from comment #4)
> > Created attachment 58462 [details]
> > Input file that triggers the test case with segmentation fault
> > 
> > This test case needs Whizard 3.1.4 to be downloaded here,
> > http://whizard.hepforge.org/whizard-3.1.4.tar.gz
> > I avoided the need for OCaml being present, just do ./configure, make, make
> > install. This will create a binary whizard, and then execute
> > whizard tauola_1.sin as attached.
> 
> ./configure
> ...
> checking for OCaml version 408000... test: -ge: unexpected operator
> < 4.08.0
> configure: error: *************************************
> configure: error: found version , too old!
> configure: error: *************************************

Just do configure with --disable-ocaml.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #7 from Jürgen Reuter <juergen.reuter at desy dot de> ---
First data point:
after the commit from Uros,
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=8bb6b2f4ae19c3aab7d7a5e5c8f5965f89d90e01
at Sun, 9 Jun 2024 10:09:13
all was still fine.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #8 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Jürgen Reuter from comment #6)
> (In reply to kargls from comment #5)
> > (In reply to Jürgen Reuter from comment #4)
> > > Created attachment 58462 [details]
> > > Input file that triggers the test case with segmentation fault
> > > 
> > > This test case needs Whizard 3.1.4 to be downloaded here,
> > > http://whizard.hepforge.org/whizard-3.1.4.tar.gz
> > > I avoided the need for OCaml being present, just do ./configure, make, make
> > > install. This will create a binary whizard, and then execute
> > > whizard tauola_1.sin as attached.
> > 
> > ./configure
> > ...
> > checking for OCaml version 408000... test: -ge: unexpected operator
> > < 4.08.0
> > configure: error: *************************************
> > configure: error: found version , too old!
> > configure: error: *************************************
> 
> Just do configure with --disable-ocaml.

Out of curiosity, what OCaml version is on your system?

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #9 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Also at the daily bump shortly after midnight morning of June 11,
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=097bc0aebaed58c11c738ea61da723cca950e5b1
the reproducer still runs fine.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #10 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Jürgen Reuter from comment #9)
> Also at the daily bump shortly after midnight morning of June 11,
> https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> h=097bc0aebaed58c11c738ea61da723cca950e5b1
> the reproducer still runs fine.

Next landmark:
also the daily bump after Tuesday June 11 in the morning of June 12,
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=7fa4b335b1ae6824893528eae56fb01ec15b6bc5
is still fine.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #11 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Jürgen Reuter from comment #10)
> (In reply to Jürgen Reuter from comment #9)
> > Also at the daily bump shortly after midnight morning of June 11,
> > https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> > h=097bc0aebaed58c11c738ea61da723cca950e5b1
> > the reproducer still runs fine.
> 
> Next landmark:
> also the daily bump after Tuesday June 11 in the morning of June 12,
> https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> h=7fa4b335b1ae6824893528eae56fb01ec15b6bc5
> is still fine.

Also the daily bump shortly after midnight of June 13 including all changes
from Wednesday, June 12,
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=158ce8ade0a98443b8fc05cbdbed5c49ee8a13b7
is still fine.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[sjames at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #12 from Sam James <sjames at gcc dot gnu.org> ---
I would just git bisect instead.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #13 from Jürgen Reuter <juergen.reuter at desy dot de> ---
The daily bump in the morning of Friday, June 14, 
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=028cd77db322d21312680c9a0a7c30565854f577
shows the segmentation fault, so the culprit comment must have happened on
Thursday, June 13, my guess would be that it's one of these two:
6 days ago      Richard Biener  tree-optimization/115385 - handle more gaps
with peelin...      commit | commitdiff | tree
6 days ago      Richard Biener  tree-optimization/114107 - avoid peeling for
gaps in...         commit | commitdiff | tree

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #14 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Jürgen Reuter from comment #13)
> The daily bump in the morning of Friday, June 14, 
> https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> h=028cd77db322d21312680c9a0a7c30565854f577
> shows the segmentation fault, so the culprit comment must have happened on
> Thursday, June 13, my guess would be that it's one of these two:
> 6 days ago 	Richard Biener	tree-optimization/115385 - handle more gaps with
> peelin... 	commit | commitdiff | tree
> 6 days ago 	Richard Biener	tree-optimization/114107 - avoid peeling for gaps
> in... 	commit | commitdiff | tree

This was still fine on Thu June 13, 05:08:
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=64cd70e315ed2cf0653cfdde96ae80c3f90a07f4

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #15 from Jürgen Reuter <juergen.reuter at desy dot de> ---
I fund the culprit commit in the gcc master, it is:
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=1fe55a1794863b5ad9eeca5062782834716016b2
by Richard Biener on the tree-optimization. Now I will try helping to get a
smaller reproducer.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #16 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jürgen Reuter from comment #15)
> I fund the culprit commit in the gcc master, it is:
> https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> h=1fe55a1794863b5ad9eeca5062782834716016b2
> by Richard Biener on the tree-optimization. Now I will try helping to get a
> smaller reproducer.

Interesting, note the other commit had r15-1309-ge575b5c56137b1 as followup
fix already.

The loop at contrib/tauola/formf.f:599 should be the problem, adding

!GCC$ novector

to it should avoid the issue (and also serve as confirmation to that).

I wonder if you can then attach enough to be able to compile the
translation unit with the respective loop.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #17 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Richard Biener from comment #16)
> (In reply to Jürgen Reuter from comment #15)
> > I fund the culprit commit in the gcc master, it is:
> > https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> > h=1fe55a1794863b5ad9eeca5062782834716016b2
> > by Richard Biener on the tree-optimization. Now I will try helping to get a
> > smaller reproducer.
> 
> Interesting, note the other commit had r15-1309-ge575b5c56137b1 as followup
> fix already.
> 
> The loop at contrib/tauola/formf.f:599 should be the problem, adding
> 
> !GCC$ novector
> 
> to it should avoid the issue (and also serve as confirmation to that).
> 
> I wonder if you can then attach enough to be able to compile the
> translation unit with the respective loop.

Indeed, adding, as you suggested, !GCC$ novector before the double do-loop 
cures the segmentation fault. I saw the follow-up commit but apparently the
daily bumps after that (e.g. from Monday morning, June 17, 0:18 am, or so,
still had this issue. I try to get a shorter reproducer, but not sure when I
will be able to do so.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jürgen Reuter from comment #17)
> (In reply to Richard Biener from comment #16)
> > (In reply to Jürgen Reuter from comment #15)
> > > I fund the culprit commit in the gcc master, it is:
> > > https://gcc.gnu.org/git/?p=gcc.git;a=commit;
> > > h=1fe55a1794863b5ad9eeca5062782834716016b2
> > > by Richard Biener on the tree-optimization. Now I will try helping to get a
> > > smaller reproducer.
> > 
> > Interesting, note the other commit had r15-1309-ge575b5c56137b1 as followup
> > fix already.
> > 
> > The loop at contrib/tauola/formf.f:599 should be the problem, adding
> > 
> > !GCC$ novector
> > 
> > to it should avoid the issue (and also serve as confirmation to that).
> > 
> > I wonder if you can then attach enough to be able to compile the
> > translation unit with the respective loop.
> 
> Indeed, adding, as you suggested, !GCC$ novector before the double do-loop 
> cures the segmentation fault. I saw the follow-up commit but apparently the
> daily bumps after that (e.g. from Monday morning, June 17, 0:18 am, or so,
> still had this issue. I try to get a shorter reproducer, but not sure when I
> will be able to do so.

If the TU with the loop can be compiled in isolation can you attach that
together with the GCC command-line triggering the issue?

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #19 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Created attachment 58476
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58476&action=edit
First independent reproducer

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[kargls at comcast dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #20 from kargls at comcast dot net ---
(In reply to Jürgen Reuter from comment #19)
> Created attachment 58476 [details]
> First independent reproducer

It appears to be a striding issue.  The loops at formf.f:507 is

       DO 206 I=1,4
          DO 206 J=1,4
             ! print *, "hadcur(i) before= ", hadcur(i)
             HADCUR(I)=
     $            HADCUR(I)+CMPLX(FIX*COEF1)*FORM1*AA(I,J) !*(PP(K,J)-PP(4,J))
             ! print *, "hadcur(i) after = ", hadcur(i)
 206   CONTINUE
C --- end of the non omega current (3 possibilities)
 201   CONTINUE

For a Fortran programmer, these loops are backwards.  If you do 

       DO 206 J=1,4
          DO 206 I=1,4
             ! print *, "hadcur(i) before= ", hadcur(i)
             HADCUR(I)=
     $            HADCUR(I)+CMPLX(FIX*COEF1)*FORM1*AA(I,J) !*(PP(K,J)-PP(4,J))
             ! print *, "hadcur(i) after = ", hadcur(i)
 206   CONTINUE
C --- end of the non omega current (3 possibilities)
 201   CONTINUE

the code compiles and executes after fixing the same issue near line 599.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
           Keywords|needs-reduction             |
             Status|WAITING                     |ASSIGNED

--- Comment #21 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  We're vectorizing the outer loop here

        do i = 1,4
           do j = 1,4
              HADCUR(I)=
     $            HADCUR(I)+CMPLX(COEF1)*FORM1*AA(I,J)*(PP(K,J)-PP(4,J))
           end do
        end do

and the issue is we're doing

=> 0x00000000006b7218 <+2504>:  movapd 0x0(%r13),%xmm1

on

(gdb) p/x $r13
$2 = 0x7fffffffb5d8

which is an unaligned address.  This is the access to AA.

The following reproduces the issue with -O2 -fno-inline:

      subroutine init(COEF1,FORM1,AA)
      double precision COEF1,X
      double complex FORM1
      double precision AA(4,4)
      COEF1=0
      FORM1=0
      AA=0
      end
      subroutine curr(HADCUR)
      double precision COEF1
      double complex HADCUR(4),FORM1
      double precision AA(4,4)
      call init(COEF1,FORM1,AA)
      do i = 1,4
         do j = 1,4
            HADCUR(I)=
     $         HADCUR(I)+CMPLX(COEF1)*FORM1*AA(I,J)
         end do
      end do
      end
      program test
        double complex HADCUR(4)
        hadcur=0
        call curr(hadcur)
      end

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

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

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

--- Comment #22 from Richard Biener <rguenth at gcc dot gnu.org> ---
Creating dr for aa[_13]
analyze_innermost: success.
        base_address: &aa
        offset from base address: (ssizetype) ((sizetype) i_35 * 8)
        constant offset from base address: -8
        step: 32
        base alignment: 16
        base misalignment: 0
        offset alignment: 8
        step alignment: 32
        base_object: aa
        Access function 0: {{0, +, 1}_1, +, 4}_2

but somehow we computed dr_info->misalignment of zero and thus we classify
this as dr_aligned.  Previously the gap code disqualified SLP use and
avoided this latent issue.

t.f:14:12: note:   inner step divides the vector alignment.
t.f:14:12: missed:   misalign = 0 bytes of ref aa[_13]

it's a bit odd - vect_compute_data_ref_alignment does

  innermost_loop_behavior *drb = vect_dr_behavior (vinfo, dr_info);

but vect_dr_behavior in this case returns &STMT_VINFO_DR_WRT_VEC_LOOP
(stmt_info) because the access is in the inner loop:

  if (loop_vinfo == NULL
      || !nested_in_vect_loop_p (LOOP_VINFO_LOOP (loop_vinfo), stmt_info))
    return &DR_INNERMOST (dr_info->dr);
  else
    return &STMT_VINFO_DR_WRT_VEC_LOOP (stmt_info);

with respect to the outer loop the access is computed misaligned through
step_alignment

$8 = {base_address = <addr_expr 0x7ffff683a140>, 
  offset = <integer_cst 0x7ffff68256c0>, init = <integer_cst 0x7ffff68256c0>, 
  step = <integer_cst 0x7ffff68256d8>, base_alignment = 16, 
  base_misalignment = 0, offset_alignment = 128, step_alignment = 8}

and misaligned with respect to the inner loop via offset_alignment:

$12 = {base_address = <addr_expr 0x7ffff68342c0>, 
  offset = <nop_expr 0x7ffff683a000>, init = <integer_cst 0x7ffff68309d8>, 
  step = <integer_cst 0x7ffff6830a50>, base_alignment = 16, 
  base_misalignment = 0, offset_alignment = 8, step_alignment = 32}

but we seem to only look at offset_alignment of one and step_alignment of
the other data piece.  It seems to me the innermost behavior should
cover the outer step via offset_alignment (but maybe I'm wrong).

Still this seems to be a quite old issue.  It seems to me we have to
consider both for the nested case, thus the 'else' arm should be
unconditional and use 'drb'.

I'm testing a patch.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #23 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Created attachment 58486
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58486&action=edit
Shorter reproducer

This is a shorter reproducer, two files of a few hundred lines each. It seems
that the problem with the vectorization appears only if the call and the double
do loop are in two different files.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #24 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jürgen Reuter from comment #23)
> Created attachment 58486 [details]
> Shorter reproducer
> 
> This is a shorter reproducer, two files of a few hundred lines each. It
> seems that the problem with the vectorization appears only if the call and
> the double do loop are in two different files.

Thanks, but see comment#21 where I already reduced a testcase.  I've posted
a fix already at
https://gcc.gnu.org/pipermail/gcc-patches/2024-June/655376.html

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #25 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Richard Biener from comment #24)
> (In reply to Jürgen Reuter from comment #23)
> > Created attachment 58486 [details]
> > Shorter reproducer
> > 
> > This is a shorter reproducer, two files of a few hundred lines each. It
> > seems that the problem with the vectorization appears only if the call and
> > the double do loop are in two different files.
> 
> Thanks, but see comment#21 where I already reduced a testcase.  I've posted
> a fix already at
> https://gcc.gnu.org/pipermail/gcc-patches/2024-June/655376.html

Oh, yes, thanks, I should've read my emails in causal order. Thanks for the
quick action. If the fix is pushed our CI will tell me Monday morning if
everything works as expected again.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #26 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Richard Biener from comment #24)
> (In reply to Jürgen Reuter from comment #23)
> > Created attachment 58486 [details]
> > Shorter reproducer
> > 
> > This is a shorter reproducer, two files of a few hundred lines each. It
> > seems that the problem with the vectorization appears only if the call and
> > the double do loop are in two different files.
> 
> Thanks, but see comment#21 where I already reduced a testcase.  I've posted
> a fix already at
> https://gcc.gnu.org/pipermail/gcc-patches/2024-June/655376.html

So your reproducer doesn't segfault with the corresponding commit, it just
produces wrong code, right?

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #27 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Jürgen Reuter from comment #26)
> (In reply to Richard Biener from comment #24)
> > (In reply to Jürgen Reuter from comment #23)
> > > Created attachment 58486 [details]
> > > Shorter reproducer
> > > 
> > > This is a shorter reproducer, two files of a few hundred lines each. It
> > > seems that the problem with the vectorization appears only if the call and
> > > the double do loop are in two different files.
> > 
> > Thanks, but see comment#21 where I already reduced a testcase.  I've posted
> > a fix already at
> > https://gcc.gnu.org/pipermail/gcc-patches/2024-June/655376.html
> 
> So your reproducer doesn't segfault with the corresponding commit, it just
> produces wrong code, right?

Ok, forgot the -fno-inline. I really need to focus on the whole content. :(

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #28 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Richard, unfortunately the fix (it seems it was committed to gcc git master on
last Friday) did not fix our problem yet. The original test case still
segfaults:
Backtrace for this error:
#0  0x7f36f52a3a6c in ???
#1  0x7f36f52a2b45 in ???
#2  0x7f36f4fe204f in ???
#3  0x7f36f5c9b323 in curr_
        at ../../../contrib/tauola/formf.f:501
#4  0x7f36f5cabc16 in dam4pi_
        at ../../../contrib/tauola/tauola.f:4106
#5  0x7f36f5cacdb6 in dph4pi_
        at ../../../contrib/tauola/tauola.f:4067
#6  0x7f36f5cb1330 in dadnew_
        at ../../../contrib/tauola/tauola.f:3667
#7  0x7f36f5cb167c in dexnew_
        at ../../../contrib/tauola/tauola.f:3592
#8  0x7f36f5cb7a4d in dexay_
        at ../../../contrib/tauola/tauola.f:525
#9  0x7f36f5cb9e3a in initdk_
        at ../../../contrib/tauola/tauola_photos_ini.f:452
#10  0x7f36f5aeebbc in __tauola_interface_MOD_wo_tauola_init_call
        at ../../../src/tauola/tauola_interface_sub.f90:903

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #29 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jürgen Reuter from comment #28)
> Richard, unfortunately the fix (it seems it was committed to gcc git master
> on last Friday) did not fix our problem yet. The original test case still
> segfaults:
> Backtrace for this error:
> #0  0x7f36f52a3a6c in ???
> #1  0x7f36f52a2b45 in ???
> #2  0x7f36f4fe204f in ???
> #3  0x7f36f5c9b323 in curr_
> 	at ../../../contrib/tauola/formf.f:501
> #4  0x7f36f5cabc16 in dam4pi_
> 	at ../../../contrib/tauola/tauola.f:4106
> #5  0x7f36f5cacdb6 in dph4pi_
> 	at ../../../contrib/tauola/tauola.f:4067
> #6  0x7f36f5cb1330 in dadnew_
> 	at ../../../contrib/tauola/tauola.f:3667
> #7  0x7f36f5cb167c in dexnew_
> 	at ../../../contrib/tauola/tauola.f:3592
> #8  0x7f36f5cb7a4d in dexay_
> 	at ../../../contrib/tauola/tauola.f:525
> #9  0x7f36f5cb9e3a in initdk_
> 	at ../../../contrib/tauola/tauola_photos_ini.f:452
> #10  0x7f36f5aeebbc in __tauola_interface_MOD_wo_tauola_init_call
> 	at ../../../src/tauola/tauola_interface_sub.f90:903

The fix wasn't yet committed.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

--- Comment #30 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:2f83ea87ee328d337f87d4430861221be9babe1e

commit r15-1582-g2f83ea87ee328d337f87d4430861221be9babe1e
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Jun 21 13:19:26 2024 +0200

    tree-optimization/115528 - fix vect alignment analysis for outer loop vect

    For outer loop vectorization of a data reference in the inner loop
    we have to look at both steps to see if they preserve alignment.

    What is special for this testcase is that the outer loop step is
    one element but the inner loop step four and that we now use SLP
    and the vectorization factor is one.

            PR tree-optimization/115528
            * tree-vect-data-refs.cc (vect_compute_data_ref_alignment):
            Make sure to look at both the inner and outer loop step
            behavior.

            * gfortran.dg/vect/pr115528.f: New testcase.

[Bug middle-end/115528] [15 regression] segmentation fault in legacy F77 code since r15-1238-g1fe55a1794863b

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115528

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #31 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.