[Bug lto/66835] New: C++ openMP test failed after switching to C++14

[Bug lto/66835] New: C++ openMP test failed after switching to C++14

[evstupac at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66835

            Bug ID: 66835
           Summary: C++ openMP test failed after switching to C++14
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: evstupac at gmail dot com
  Target Milestone: ---

The following test:
#define max(a, b)   ( (a) > (b) ? (a) : (b) ) 

float a[4] = {0, -1.2, 7, 0.1}; 

int main() 
{ 
#pragma omp simd 
  for (int j = 0; j < 4; j++) 
    { 
      float t1 = 0.1; 
      a[j] = max(t1, a[j]); 
    } 
  return (int)(a[1] - a[3]); 
} 

fails with ICE after recent switch to std=c++14

Compiled with "-O2 -flto -fopenmp -std=c++14"

The test began to fail after:
commit 23a92fc764dc04a0248a570bba74db0a7f7d843d
Author: tbsaunde <tbsaunde@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Tue Nov 11 02:31:00 2014 +0000

[Bug lto/66835] C++ openMP test failed after switching to C++14

[evstupac at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66835

--- Comment #1 from Stupachenko Evgeny <evstupac at gmail dot com> ---
wrong revision bisected. Was just bootstrap fail. Searching for really bad.

[Bug lto/66835] C++ openMP test failed after switching to C++14

[evstupac at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66835

Stupachenko Evgeny <evstupac at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |izamyatin at gmail dot com,
                   |                            |jakub at redhat dot com

--- Comment #2 from Stupachenko Evgeny <evstupac at gmail dot com> ---
The following commit made the test compiled with "-O2 -flto -fopenmp
-std=c++14" fail with ICE:

commit 0c368492c85091d7b90cade269c45aba4cee77f5
Author: jakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Fri Nov 14 19:41:00 2014 +0000

        * tree-ssa.dce.c (eliminate_unnecessary_stmts): Eliminate
        IFN_GOMP_SIMD_LANE without lhs as useless.


    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@217584
138bc75d-0d04-0410-961f-82ee72b054a4


ICE details:

lto1: internal compiler error: in operator[], at vec.h:736
0xc0a220 vec<tree_node*, va_heap, vl_embed>::operator[](unsigned int)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/vec.h:736
0xc0a220 vec<tree_node*, va_heap, vl_ptr>::operator[](unsigned int)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/vec.h:1202
0xc0a220 streamer_tree_cache_get_tree
        /export/users/evstupac/gcc/git/check2/gcc/gcc/tree-streamer.h:112
0xc0a220 streamer_get_pickled_tree(lto_input_block*, data_in*)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/tree-streamer-in.c:1102
0x903af4 lto_input_tree_1(lto_input_block*, data_in*, LTO_tags, unsigned int)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1296
0x903dba lto_input_tree(lto_input_block*, data_in*)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1342
0xc091df lto_input_ts_decl_minimal_tree_pointers
        /export/users/evstupac/gcc/git/check2/gcc/gcc/tree-streamer-in.c:697
0xc091df streamer_read_tree_body(lto_input_block*, data_in*, tree_node*)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/tree-streamer-in.c:1043
0x9034ff lto_read_tree_1
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1172
0x9039e4 lto_read_tree
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1206
0x9039e4 lto_input_tree_1(lto_input_block*, data_in*, LTO_tags, unsigned int)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1325
0x903d20 lto_input_scc(lto_input_block*, data_in*, unsigned int*, unsigned
int*)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1230
0x903d94 lto_input_tree(lto_input_block*, data_in*)
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1340
0x905528 input_cfg
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:739
0x905528 input_function
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:950
0x905528 lto_read_body_or_constructor
        /export/users/evstupac/gcc/git/check2/gcc/gcc/lto-streamer-in.c:1101
0x6303f9 cgraph_node::get_body()
        /export/users/evstupac/gcc/git/check2/gcc/gcc/cgraph.c:3170

[Bug lto/66835] C++ openMP test failed after switching to C++14

[evstupac at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66835

--- Comment #3 from Stupachenko Evgeny <evstupac at gmail dot com> ---
The same reproduced on GCC 5.

[Bug lto/66835] C++ openMP test failed after switching to C++14

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66835

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Even though this bug is older than PR 67452, PR 67452 has the commit which
fixed the bug already referenced so closing this bug as a dup of bug 67452.

*** This bug has been marked as a duplicate of bug 67452 ***