[Bug target/111941] New: RISC-V ICE: in merge, at config/riscv/riscv-vsetvl.cc:1996

["patrick at rivosinc dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111941

            Bug ID: 111941
           Summary: RISC-V ICE: in merge, at
                    config/riscv/riscv-vsetvl.cc:1996
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: patrick at rivosinc dot com
  Target Milestone: ---

Created attachment 56180
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56180&action=edit
-freport-bug output

First bad commit: r14-4773-g29331e72d0c
Confirmed to still be present on trunk: r14-4809-g55731b59e60

Building newlib 4.1.0 fails on ldtoa.c

https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=newlib/libc/stdlib/ldtoa.c;h=1cc97151afb693b04c864243a4466038b06ac94f;hb=415fdd4279b85eeec9d54775ce13c5c412451e08

creduce'd testcase:

./bin/riscv64-unknown-elf-gcc -fno-builtin -O2 -march=rv64gv_zbb -mabi=lp64d -S
-o test.S red.c
./bin/riscv64-unknown-elf-gcc -fno-builtin -O2 -march=rv32gv_zbb -mabi=ilp32d
-S -o test.S red.c

> cat red.c
typedef struct {
  short a[0]
} b;
c;
d[];
b e;
*f;
j() {
  short *g = d;
  int h;
  unsigned short i;
  for (; h < 10; h++)
    i |= *f++;
  if (i)
    i = 1;
  h = 0;
  for (; h < 10; h++)
    g[h] = e.a[h];
  c = i;
}