[Bug c++/113178] New: ice in find_uses_to_rename_use

["dcb314 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113178

            Bug ID: 113178
           Summary: ice in find_uses_to_rename_use
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

This C++ source code:

struct PixelWeight {
  int m_SrcStart;
  int m_Weights[];
};
struct CWeightTable {
  int *GetValueFromPixelWeight(PixelWeight *, int) const;
};
char ContinueStretchHorz_dest_scan;
struct CStretchEngine {
  bool ContinueStretchHorz();
  CWeightTable m_WeightTable;
};
int *CWeightTable::GetValueFromPixelWeight(PixelWeight *pWeight,
                                           int index) const {
  long __trans_tmp_1;
  if (index < pWeight->m_SrcStart)
    return __trans_tmp_1 ? &pWeight->m_Weights[pWeight->m_SrcStart] : nullptr;
}
bool CStretchEngine::ContinueStretchHorz() {
  {
    PixelWeight pPixelWeights;
    int dest_g_m;
    for (int j; j; j++) {
      int pWeight = *m_WeightTable.GetValueFromPixelWeight(&pPixelWeights, j);
      dest_g_m += pWeight;
    }
    ContinueStretchHorz_dest_scan = dest_g_m;
  }
}

when compiled by recent gcc trunk, does this:

cvise $ ~/gcc/results.20231227.asan.ubsan/bin/g++ -c -O3 -w  bug995.cc
cvise $ ~/gcc/results.20231227.asan.ubsan/bin/g++ -c -O3 -w -march=znver3
bug995.cc
during GIMPLE pass: vect
bug995.cc: In member function ‘bool CStretchEngine::ContinueStretchHorz()’:
bug995.cc:19:6: internal compiler error: Segmentation fault
   19 | bool CStretchEngine::ContinueStretchHorz() {
      |      ^~~~~~~~~~~~~~
0x11e1b39 crash_signal(int)
        ../../trunk.20210101/gcc/toplev.cc:316
0x1381b98 find_uses_to_rename_use(basic_block_def*, tree_node*, bitmap_head**,
bitmap_head*)
        ../../trunk.20210101/gcc/tree-ssa-loop-manip.cc:414