Hi! Now that the C++ FE supports these attributes, but not through registering them in the attributes tables (they work quite differently from other attributes), this teaches c_common_has_attributes about those.
Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk. 2021-07-23 Jakub Jelinek <ja...@redhat.com> * c-lex.c (c_common_has_attribute): Call canonicalize_attr_name also on attr_id. Return 1 for omp::directive or omp::sequence in C++11 and later. * c-c++-common/gomp/attrs-1.c: New test. * c-c++-common/gomp/attrs-2.c: New test. * c-c++-common/gomp/attrs-3.c: New test. --- gcc/c-family/c-lex.c.jj 2021-05-21 10:34:09.046563955 +0200 +++ gcc/c-family/c-lex.c 2021-07-22 15:16:37.340412532 +0200 @@ -338,7 +338,20 @@ c_common_has_attribute (cpp_reader *pfil tree attr_id = get_identifier ((const char *) cpp_token_as_text (pfile, nxt_token)); - attr_name = build_tree_list (attr_ns, attr_id); + attr_id = canonicalize_attr_name (attr_id); + if (c_dialect_cxx ()) + { + /* OpenMP attributes need special handling. */ + if ((flag_openmp || flag_openmp_simd) + && is_attribute_p ("omp", attr_ns) + && (is_attribute_p ("directive", attr_id) + || is_attribute_p ("sequence", attr_id))) + result = 1; + } + if (result) + attr_name = NULL_TREE; + else + attr_name = build_tree_list (attr_ns, attr_id); } else { --- gcc/testsuite/c-c++-common/gomp/attrs-1.c.jj 2021-07-22 14:34:26.718586059 +0200 +++ gcc/testsuite/c-c++-common/gomp/attrs-1.c 2021-07-22 15:16:00.389926789 +0200 @@ -0,0 +1,146 @@ +/* { dg-do compile } */ +/* { dg-options "-fopenmp" } */ + +#if __has_attribute(omp::directive) +#ifndef __cplusplus +#error omp::directive supported in C +#endif +#else +#ifdef __cplusplus +#error omp::directive not supported in C++ +#endif +#endif + +#if __has_attribute(omp::sequence) +#ifndef __cplusplus +#error omp::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error omp::sequence not supported in C++ +#endif +#endif + +#if __has_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_cpp_attribute(omp::directive) +#ifndef __cplusplus +#error omp::directive supported in C +#endif +#else +#ifdef __cplusplus +#error omp::directive not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::sequence) +#ifndef __cplusplus +#error omp::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error omp::sequence not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_attribute(__omp__::__directive__) +#ifndef __cplusplus +#error __omp__::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__directive__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::__sequence__) +#ifndef __cplusplus +#error __omp__::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__sequence__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::__directive__) +#ifndef __cplusplus +#error __omp__::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__directive__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::__sequence__) +#ifndef __cplusplus +#error __omp__::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__sequence__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_attribute(omp::__directive__) +#ifndef __cplusplus +#error omp::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error omp::__directive__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::sequence) +#ifndef __cplusplus +#error __omp__::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::sequence not supported in C++ +#endif +#endif + +#if __has_attribute(omp::__unknown__) +#error omp::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::directive) +#ifndef __cplusplus +#error __omp__::directive supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::directive not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::__sequence__) +#ifndef __cplusplus +#error omp::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error omp::__sequence__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::unknown) +#error __omp__::unknown supported +#endif --- gcc/testsuite/c-c++-common/gomp/attrs-2.c.jj 2021-07-22 14:34:34.508477846 +0200 +++ gcc/testsuite/c-c++-common/gomp/attrs-2.c 2021-07-22 15:16:18.635672852 +0200 @@ -0,0 +1,146 @@ +/* { dg-do compile } */ +/* { dg-options "-fno-openmp -fopenmp-simd" } */ + +#if __has_attribute(omp::directive) +#ifndef __cplusplus +#error omp::directive supported in C +#endif +#else +#ifdef __cplusplus +#error omp::directive not supported in C++ +#endif +#endif + +#if __has_attribute(omp::sequence) +#ifndef __cplusplus +#error omp::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error omp::sequence not supported in C++ +#endif +#endif + +#if __has_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_cpp_attribute(omp::directive) +#ifndef __cplusplus +#error omp::directive supported in C +#endif +#else +#ifdef __cplusplus +#error omp::directive not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::sequence) +#ifndef __cplusplus +#error omp::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error omp::sequence not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_attribute(__omp__::__directive__) +#ifndef __cplusplus +#error __omp__::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__directive__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::__sequence__) +#ifndef __cplusplus +#error __omp__::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__sequence__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::__directive__) +#ifndef __cplusplus +#error __omp__::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__directive__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::__sequence__) +#ifndef __cplusplus +#error __omp__::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::__sequence__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_attribute(omp::__directive__) +#ifndef __cplusplus +#error omp::__directive__ supported in C +#endif +#else +#ifdef __cplusplus +#error omp::__directive__ not supported in C++ +#endif +#endif + +#if __has_attribute(__omp__::sequence) +#ifndef __cplusplus +#error __omp__::sequence supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::sequence not supported in C++ +#endif +#endif + +#if __has_attribute(omp::__unknown__) +#error omp::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::directive) +#ifndef __cplusplus +#error __omp__::directive supported in C +#endif +#else +#ifdef __cplusplus +#error __omp__::directive not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(omp::__sequence__) +#ifndef __cplusplus +#error omp::__sequence__ supported in C +#endif +#else +#ifdef __cplusplus +#error omp::__sequence__ not supported in C++ +#endif +#endif + +#if __has_cpp_attribute(__omp__::unknown) +#error __omp__::unknown supported +#endif --- gcc/testsuite/c-c++-common/gomp/attrs-3.c.jj 2021-07-22 14:34:56.393173843 +0200 +++ gcc/testsuite/c-c++-common/gomp/attrs-3.c 2021-07-22 14:58:17.525708003 +0200 @@ -0,0 +1,74 @@ +/* { dg-do compile } */ +/* { dg-options "-fno-openmp -fno-openmp-simd" } */ + +#if __has_attribute(omp::directive) +#error omp::directive supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(omp::sequence) +#error omp::sequence supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_cpp_attribute(omp::directive) +#error omp::directive supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(omp::sequence) +#error omp::sequence supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(omp::unknown) +#error omp::unknown supported +#endif + +#if __has_attribute(__omp__::__directive__) +#error __omp__::__directive__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(__omp__::__sequence__) +#error __omp__::__sequence__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::__directive__) +#error __omp__::__directive__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(__omp__::__sequence__) +#error __omp__::__sequence__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(__omp__::__unknown__) +#error __omp__::__unknown__ supported +#endif + +#if __has_attribute(omp::__directive__) +#error omp::__directive__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(__omp__::sequence) +#error __omp__::sequence supported even when -fno-openmp{,-simd} +#endif + +#if __has_attribute(omp::__unknown__) +#error omp::__unknown__ supported +#endif + +#if __has_cpp_attribute(__omp__::directive) +#error __omp__::directive supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(omp::__sequence__) +#error omp::__sequence__ supported even when -fno-openmp{,-simd} +#endif + +#if __has_cpp_attribute(__omp__::unknown) +#error __omp__::unknown supported +#endif Jakub