[Bug c/104178] New: -fcompare-debug failure at -O3 -m32

[Bug c/104178] New: -fcompare-debug failure at -O3 -m32

[cnsun at uwaterloo dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

            Bug ID: 104178
           Summary: -fcompare-debug failure at -O3 -m32
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: cnsun at uwaterloo dot ca
  Target Milestone: ---

$ gcc-trunk small.c -w -m32 -fcompare-debug -O3
gcc-trunk: error: small.c: ‘-fcompare-debug’ failure (length)
$ cat small.c
static int a, g, h, k, l, m, p, r, s, u, w, z, aa, ab, ac, ad;
char b, ae, af;
struct c {
  int d;
  int e;
} e[1];
static char f;
static short i;
static struct c j, x;
static unsigned n;
int *o, *t;
static char q;
int v;
int y;
int ag;
int ah;
int ai;
int aj;
int ak;
static char al() {
  int am[] = {0, 1, 9, 6, 3, 4, 3, 0, 3, 4, 3, 9, 0, 6, 1, 1, 6, 0, 2, 4,
              6, 4, 2, 4, 6, 1, 1, 6, 0, 9, 9, 0, 3, 0, 3, 4, 3, 0, 3};
  int an = 8, ao = r;
  int c[] = {2, 2, 2, 2, 2};
  char ap;
  if (ao) {
    ap = af;
    for (; t; t++)
      printf("index = \n");
  }
  af = r = ao;
  int *aq = 0;
  {
    int *b[] = {o, o, o, o, o, o, o, o, o, o, o, o, o};
    if (r) {
      struct c c[] = {*e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e, *e,
                      *e, *e, *e, *e, *e, *e, *e, *e};
      k = ab;
      for (; u;) {
        struct c d = {1};
        ak = 0;
        int ar = f ^ p;
      as:
        if (ar) {
          printf("", p);
          p = a ^ p;
        }
      }
    }
    if (z)
      goto at;
    a = l;
    an = 5;
  }
  if (f) {
    int *au[10];
    aa = 0;
    for (; aa < 10; aa++)
      au[aa] = &an;
    for (; m;)
      ;
    a = r;
  }
  if (g)
    f = 1;
  for (; f;) {
    while (an < 5 || i)
      ae = q;
    int c[] = {*o, *o, *o, *o, *o, *o, *o, *o, *o, *o, *o, *o, *o};
    if (w)
      for (;;) {
        if (r)
          break;
        a = a ^ printf(&b);
        for (; ac; ac++)
          ;
      }
    else
      *aq = r;
    ai = r;
    n = (an || ~r) + n || j.d;
    if (r)
      a = a ^ 5;
    if (s)
      printf(&b);
    printf("", s);
    if (p) {
      s = 3;
      for (; s;)
        if (ap)
          ap = 0;
    }
    int av = h ^ q, aw = j.e ^ av;
    while (h++) {
      a = a ^ 5;
      if (k)
        printf(&b);
    }
    if (aw)
      v = j.e ^ q;
  at:
    b = ag = w = 0;
    if (f)
      goto ax;
    z = h;
    a = k;
    if (n)
      printf("", m);
    if (k) {
      printf("", k);
      m = n & m + k;
    }
    a = j.d;
    u = n + l;
    if (ah)
      break;
  ay:
    if (l)
      q = j.d;
  }
  int az = i || m;
  int ba = g || f;
  g = i = az;
  *e = x;
  char bb = n & m & p || r;
ax:
  if (y) {
    printf("", ba);
    goto as;
  }
  af = bb;
  b = i | n;
  if (j.d)
    printf("", e);
  char bc = p & n | i;
  n = bc;
  int bd = l & m;
  m = bd;
  if (aj) {
    printf("", ad);
    m = l;
    goto ay;
  }
  l = f;
  j = e[0];
}
int main() { al(); }
$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/scratch/software/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/12.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /tmp/tmp.OLkXuGPSxC-gcc-builder/gcc/configure
--enable-languages=c,c++,lto --enable-checking-yes --enable-multiarch
--prefix=/scratch/software/gcc-trunk --disable-bootstrap
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 12.0.1 20220121 (experimental) [master -gcaca8eddd] (GCC) 
$

[Bug c/104178] -fcompare-debug failure at -O3 -m32

[cnsun at uwaterloo dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

--- Comment #1 from Chengnian Sun <cnsun at uwaterloo dot ca> ---
Sorry for the long test case. I tried my best to reduce it. The reported test
program is the best I could get.

[Bug middle-end/104178] [12 Regreession] -fcompare-debug failure at -O3 -m32

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0
            Version|unknown                     |12.0
            Summary|-fcompare-debug failure at  |[12 Regreession]
                   |-O3 -m32                    |-fcompare-debug failure at
                   |                            |-O3 -m32
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-01-22
     Ever confirmed|0                           |1

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.

[Bug middle-end/104178] [12 Regreession] -fcompare-debug failure at -O3 -m32

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r12-4790-g4b3a325f07acebf47e82de227ce1d5ba62f5bcae

[Bug tree-optimization/104178] [12 Regreession] -fcompare-debug failure at -O3 -m32

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|middle-end                  |tree-optimization

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The first difference shows up in 194t.dom3 .

[Bug tree-optimization/104178] [12 Regreession] -fcompare-debug failure at -O3 -m32

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|12.0                        |12.2

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 12.1 is being released, retargeting bugs to GCC 12.2.

[Bug tree-optimization/104178] [12 Regreession] -fcompare-debug failure at -O3 -m32

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104178

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|12.3                        |12.4

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.3 is being released, retargeting bugs to GCC 12.4.