OpenMP: 'allocate' directive - fixes for 'alignof' and [[omp::decl]]

Fixed a check to permit [[omp::decl(allocate,...)]] parsing in C.

Additionaly, we discussed that 'allocate align' should not affect
'alignof' to avoid issues like with:

  int a;
  _Alignas(_Alignof(a)) int b;
  #pragma omp allocate(a) align(128)
  _Alignas(_Alignof(a)) int c;

Thus, the alignment is no longer set in the C and Fortran front ends,
but for static variables now in varpool_node::finalize_decl.
(For stack variables, the alignment is handled in gimplify_bind_expr.)

NOTE: 'omp allocate' is not yet supported in C++.

gcc/c/ChangeLog:

	* c-parser.cc (c_parser_omp_allocate): Only check scope if
	not in_omp_decl_attribute. Remove setting the alignment.

gcc/ChangeLog:

	* cgraphunit.cc (varpool_node::finalize_decl): Set alignment
	based on OpenMP's 'omp allocate' attribute/directive.

gcc/fortran/ChangeLog:

	* trans-decl.cc (gfc_finish_var_decl): Remove setting the alignment.

libgomp/ChangeLog:

	* libgomp.texi (Memory allocation): Mention (non-)effect of 'align'
	on _Alignof.
	* testsuite/libgomp.c/allocate-7.c: New test.

gcc/testsuite/ChangeLog:

	* c-c++-common/gomp/allocate-18.c: Check that alignof is unaffected
	by 'omp allocate'.
	* c-c++-common/gomp/allocate-19.c: Likewise.

2 files changed, 8 insertions, 8 deletions

diff --git a/gcc/testsuite/c-c++-common/gomp/allocate-18.c b/gcc/testsuite/c-c++-common/gomp/allocate-18.c
index 4182f7e..93c5aca 100644
--- a/gcc/testsuite/c-c++-common/gomp/allocate-18.c
+++ b/gcc/testsuite/c-c++-common/gomp/allocate-18.c
@@ -17,14 +17,14 @@ typedef enum omp_allocator_handle_t
 
 void test0 ()
 {
-  int A1[5];
+  int A1[5], B1[5];
   #pragma omp allocate(A1) align(128) allocator(omp_default_mem_alloc)
   /* { dg-message "sorry, unimplemented: '#pragma omp allocate' not yet supported" "" { target c++ } .-1 } */
 
   #ifndef __cplusplus
-    _Static_assert (_Alignof(A1) == 128, "wrong alignment");
+    _Static_assert (_Alignof(A1) == _Alignof(B1), "wrong alignment");
   #elif __cplusplus >= 201103L
-     static_assert (alignof(A1) == 128, "wrong alignment");  /* { dg-bogus "static assertion failed: wrong alignment" "" { xfail { c++ && { ! c++98_only } } } } */
+     static_assert (alignof(A1) == alignof(B1), "wrong alignment"); 
   #endif
 }
 
diff --git a/gcc/testsuite/c-c++-common/gomp/allocate-19.c b/gcc/testsuite/c-c++-common/gomp/allocate-19.c
index ad3493d..5c5fc00 100644
--- a/gcc/testsuite/c-c++-common/gomp/allocate-19.c
+++ b/gcc/testsuite/c-c++-common/gomp/allocate-19.c
@@ -19,14 +19,14 @@ typedef enum omp_allocator_handle_t
   __omp_allocator_handle_t_max__ = __UINTPTR_MAX__
 } omp_allocator_handle_t;
 
-static int A1[5] = {1,2,3,4,5};
+static int A1[5] = {1,2,3,4,5}, B1[5];
 #pragma omp allocate(A1) align(128) allocator(omp_default_mem_alloc)
 /* { dg-message "sorry, unimplemented: '#pragma omp allocate' not yet supported" "" { target c++ } .-1 } */
 
 #ifndef __cplusplus
-_Static_assert (_Alignof(A1) == 128, "wrong alignment");
+_Static_assert (_Alignof(A1) == _Alignof(B1), "wrong alignment");
 #elif __cplusplus >= 201103L
-static_assert (alignof(A1) == 128, "wrong alignment");  /* { dg-bogus "static assertion failed: wrong alignment" "" { xfail { c++ && { ! c++98_only } } } } */
+static_assert (alignof(A1) == alignof(B1), "wrong alignment");
 #endif
 
 
@@ -49,9 +49,9 @@ get ()
   /* { dg-message "sorry, unimplemented: '#pragma omp allocate' not yet supported" "" { target c++ } .-1 } */
 
 #ifndef __cplusplus
-  _Static_assert (_Alignof(q) == 1024, "wrong alignment");
+  _Static_assert (_Alignof(q) == _Alignof(int), "wrong alignment");
 #elif __cplusplus >= 201103L
-  static_assert (alignof(q) == 1024, "wrong alignment");  /* { dg-bogus "static assertion failed: wrong alignment" "" { xfail { c++ && { ! c++98_only } } } } */
+  static_assert (alignof(q) == alignof(int), "wrong alignment");
 #endif
 
   q += 1;