[Bug tree-optimization/98069] New: Miscompilation with -O3

["vsevolod.livinskij at frtk dot ru" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98069

            Bug ID: 98069
           Summary: Miscompilation with -O3
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vsevolod.livinskij at frtk dot ru
  Target Milestone: ---

Reproducer:
//func.cpp
extern long long var_3;
extern short var_8;
extern int var_17;
extern short arr_165[];
long c(long e, long f) { return f ? e : f; }
void test() {
    for (int b = 0; b < 19; b = var_17)
        for (int d = int(~c(-2147483647 - 1, var_3)) - 2147483647; d < 22; d++)
            arr_165[d] = var_8;
}

//driver.cpp 
#include <stdio.h>

long long int var_3 = -166416893043554447LL;
short var_8 = (short)27092;
unsigned int var_17 = 75036300U;
short arr_165[23];

void test();

int main() {
    for (size_t i_3 = 0; i_3 < 23; ++i_3)
        arr_165[i_3] = (short)-8885;
    test();
    printf("%d\n", arr_165[0]);
}

>$ g++ -O3 func.cpp driver.cpp && ./a.out
Segmentation fault (core dumped)
>$ g++ -O2 func.cpp driver.cpp && ./a.out
27092

gcc version 11.0.0 20201126 (beb9afcaf1466996a301c778596c5df209e7913c)