[Bug tree-optimization/67055] [5 Regression] Segmentation fault in fold_builtin_alloca_with_align in tree-ssa-ccp.c

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67055

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[5/6 Regression]            |[5 Regression] Segmentation
                   |Segmentation fault in       |fault in
                   |fold_builtin_alloca_with_al |fold_builtin_alloca_with_al
                   |ign in tree-ssa-ccp.c       |ign in tree-ssa-ccp.c

--- Comment #13 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Another testcase:

trippels@gcc2-power8 ~ % cat syn.i
struct list_head
{
  struct list_head *prev;
};
extern void __wait_rcu_gp (void*);
const int a = sizeof 0;
static inline __attribute__ ((always_inline no_instrument_function)) void
rcu_barrier_sched (void)
{
  struct list_head b[a];
  __wait_rcu_gp (b);
}

static inline __attribute__ ((always_inline no_instrument_function)) void
rcu_barrier (void)
{
  rcu_barrier_sched ();
}

struct
{
  void *wait;
} c[] = { rcu_barrier, rcu_barrier_sched };

trippels@gcc2-power8 ~ % /home/trippels/gcc_5/usr/local/bin/gcc -c -O2 syn.i
syn.i: In function ‘rcu_barrier_sched’:
syn.i:8:1: internal compiler error: Segmentation fault
 rcu_barrier_sched (void)
 ^
0x107e9053 crash_signal
        ../../gcc/gcc/toplev.c:383
0x10937a64 tree_check
        ../../gcc/gcc/tree.h:2850
0x10937a64 fold_builtin_alloca_with_align
        ../../gcc/gcc/tree-ssa-ccp.c:2067
0x10937a64 ccp_fold_stmt
        ../../gcc/gcc/tree-ssa-ccp.c:2172
0x109d85a3
substitute_and_fold_dom_walker::before_dom_children(basic_block_def*)
        ../../gcc/gcc/tree-ssa-propagate.c:1177
0x10dd228b dom_walker::walk(basic_block_def*)
        ../../gcc/gcc/domwalk.c:188
0x109d7993 substitute_and_fold(tree_node* (*)(tree_node*), bool
(*)(gimple_stmt_iterator*), bool)
        ../../gcc/gcc/tree-ssa-propagate.c:1272
0x1092f0eb ccp_finalize
        ../../gcc/gcc/tree-ssa-ccp.c:941
0x1092f0eb do_ssa_ccp
        ../../gcc/gcc/tree-ssa-ccp.c:2382
0x1092f0eb execute
        ../../gcc/gcc/tree-ssa-ccp.c:2414
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.