craycc: internal compiler error on the 6.0 combined construct target loop instead of a diagnostic

// # Draft finding: omp60-c-directive-target_loop on cce21
//
// - compiler: cce21
// - toolchain: cce21; arch: gfx942; machine: tuolumne; memory mode: unified; opt: -O2
// - program: catalog omp60-c-directive-target_loop (c, version 60, sha256 f7b09fc0585b20d6)
// - expected: None (None; )
// - actual: ice  (ice: PLEASE submit a bug report to HPE at https://support.hpe.com/ and include the crash backtrace, preprocessed source, and associated run script.)
// - verdict: compiler_bug by rule R10-compile-ice: an internal compiler error (or the compiler rejecting code it generated) on a legal program: always the compiler's defect
// - reason: 
// - citations: RUL-COMPILE-TIME (rulings.md)
// - legality: legal (legal by construction: offload.engine.gen / c_gen / acc_gen check every program against the catalog rules and the offload scope as it is built (no compiler))
// - witnesses: none
// - withdrawn: none
//
// Generated by compliance.c_gen (OpenMP 6.0, C11): the C port (offload.engine.f2c) of omp60-directive-target_loop. Do not edit.
// id: omp60-c-directive-target_loop
// primary atom: omp.directive.target_loop
// legal: yes
// observable: yes
// ran_on_host: probe (a target region just before the region of interest, which may not call the OpenMP API)
// evidence: construct
// needs: none
// std: c11
#include <stdio.h>
#include <stdbool.h>
#include <omp.h>

enum { n = 64 };
int on_dev = 0;
#pragma omp declare target(on_dev)

int main(void) {
  int a[n];
  int b[n];
  int ref[n];
  int host_flag;
  bool ok;
  for (int i = 1; i <= n; i++) {
    a[i - 1] = i;
    b[i - 1] = 0;
    ref[i - 1] = 2 * i + 1;
  }
  host_flag = 1;
  #pragma omp target map(tofrom: host_flag)
  {
    host_flag = (omp_is_initial_device() ? 1 : 0);
    on_dev = 1;
  }
  #pragma omp target loop map(to: a) map(from: b)
  for (int i = 1; i <= n; i++) {
    b[i - 1] = 2 * a[i - 1] + on_dev;
  }
  bool t1_ = true;
  for (int k2_ = 0; k2_ < n; k2_++)
    t1_ = t1_ && (b[k2_] == 2 * a[k2_]);
  if (t1_) host_flag = 1;
  bool t3_ = true;
  for (int k4_ = 0; k4_ < n; k4_++)
    t3_ = t3_ && (b[k4_] == ref[k4_]);
  ok = t3_;
  printf("RESULT ran_on_host=%d check=%s\n", host_flag, ok ? "pass" : "fail");
  return 0;
}
// spec (requirement): OpenMP 6.0 defines target loop as a combined construct, whose semantics are those of a target
//   construct holding exactly one loop construct.
// "The semantics of combined constructs are identical to that of explicitly specifying the first construct containing
//   one instance of the second construct and no other statements." (6.0 §19.3 p.531 l.2-3)
// spec (requirement): A compound directive name is a combined directive name when the second construct can be
//   immediately nested in the first.
// "If the construct named by directive-name-B can be immediately nested inside the construct named by
//   directive-name-A, the compound-directive name is a combined-directive name" (6.0 §19.1 p.525 l.11-13)
// spec (this program): target loop is a combined construct of the 6.0 grammar and must behave as target with one loop
//   construct; the compiler gives an internal error instead of either compiling it or diagnosing it as unsupported.