Hi! The (mini)pass to diagnose invalid OpenMP/OpenACC/Cilk+ constructs wasn't mistakenly run for -fopenmp-simd, so non-conforming simd constructs weren't diagnosed, but could easily ICE later on, because we assume the body of the loop is a structured block (single entry, single exit, no branches into it or out of it, no exceptions thrown out of it etc.).
Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk so far, queued for backporting. 2017-08-03 Jakub Jelinek <ja...@redhat.com> PR middle-end/81052 * omp-low.c (diagnose_sb_0): Handle flag_openmp_simd like flag_openmp. (pass_diagnose_omp_blocks::gate): Enable also for flag_openmp_simd. * c-c++-common/pr81052.c: New test. --- gcc/omp-low.c.jj 2017-07-06 20:31:32.000000000 +0200 +++ gcc/omp-low.c 2017-08-02 12:52:47.608735787 +0200 @@ -9083,7 +9083,7 @@ diagnose_sb_0 (gimple_stmt_iterator *gsi } if (kind == NULL) { - gcc_checking_assert (flag_openmp); + gcc_checking_assert (flag_openmp || flag_openmp_simd); kind = "OpenMP"; } @@ -9343,7 +9343,7 @@ public: /* opt_pass methods: */ virtual bool gate (function *) { - return flag_cilkplus || flag_openacc || flag_openmp; + return flag_cilkplus || flag_openacc || flag_openmp || flag_openmp_simd; } virtual unsigned int execute (function *) { --- gcc/testsuite/c-c++-common/pr81052.c.jj 2017-08-02 12:59:28.092223248 +0200 +++ gcc/testsuite/c-c++-common/pr81052.c 2017-08-02 13:00:30.603510773 +0200 @@ -0,0 +1,28 @@ +/* PR middle-end/81052 */ +/* { dg-do compile } */ +/* { dg-options "-fopenmp-simd -O2" } */ + +int +foo (int x, int y) +{ + int i; +#pragma omp simd + for (i = x; i < y; ++i) + return 0; /* { dg-error "invalid branch to/from OpenMP structured block" } */ + return 1; +} + +#ifdef __cplusplus +template <typename T> +T +bar (T x, T y) +{ + T i; +#pragma omp simd + for (i = x; i < y; ++i) + return 0; /* { dg-error "invalid branch to/from OpenMP structured block" "" { target c++ } } */ + return 1; +} + +int x = bar (1, 7); +#endif Jakub