[Bug c/101626] New: [12 Regression] ICE in verify_sra_access_forest, at tree-sra.c:2376

[gscfq--- via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101626

            Bug ID: 101626
           Summary: [12 Regression] ICE in verify_sra_access_forest, at
                    tree-sra.c:2376
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gs...@t-online.de
  Target Milestone: ---

Changed between 20210502 and 20210509.
(gcc configured with --enable-checking=yes)

Affects a bunch of testsuite files at -O1+,
e.g. pr36373*.c, pr39120.c, pr50444.c :


$ cat pr39120.c
struct X { int *p; } x;

struct X __attribute__((noinline))
foo(int *p) { struct X x; x.p = p; return x; }

void __attribute((noinline))
bar() { *x.p = 1; }

extern void abort (void);
int main()
{
  int i = 0;
  x = foo(&i);
  bar();
  if (i != 1)
    abort ();
  return 0;
}


$ gcc-12-20210725 -c pr39120.c -O2 -fsso-struct=big-endian
during GIMPLE pass: esra
pr39120.c: In function 'foo':
pr39120.c:18:1: internal compiler error: in verify_sra_access_forest, at
tree-sra.c:2376
   18 | }
      | ^
0xee585c verify_sra_access_forest(access*)
        ../../gcc/tree-sra.c:2376
0xee5af1 verify_all_sra_access_forests()
        ../../gcc/tree-sra.c:2420
0xee9d45 analyze_all_variable_accesses
        ../../gcc/tree-sra.c:3480
0xeea7c6 perform_intra_sra
        ../../gcc/tree-sra.c:4564