[gcc/devel/omp/gcc-14] openacc: fix ICE for non-decl expression in non-contiguous array base-pointer

[Paul-Antoine Arras]

https://gcc.gnu.org/g:151fc161d0ed640048444ca18f9325e3d2e03e99

commit 151fc161d0ed640048444ca18f9325e3d2e03e99
Author: Chung-Lin Tang <cltang@codesourcery.com>
Date:   Thu Aug 19 16:17:02 2021 +0800

    openacc: fix ICE for non-decl expression in non-contiguous array base-pointer
    
    Currently, we do not support cases like struct-members as the base-pointer
    for an OpenACC non-contiguous array. Mark such cases as unsupported in the
    C/C++ front-ends, instead of ICEing on them.
    
    gcc/c/ChangeLog:
    
            * c-typeck.cc (handle_omp_array_sections_1): Robustify non-contiguous
            array check and reject non-DECL base-pointer cases as unsupported.
    
    gcc/cp/ChangeLog:
    
            * semantics.cc (handle_omp_array_sections_1): Robustify non-contiguous
            array check and reject non-DECL base-pointer cases as unsupported.

Diff:
---
 gcc/c/ChangeLog.omp  |  5 +++++
 gcc/c/c-typeck.cc    | 19 ++++++++++++++++---
 gcc/cp/ChangeLog.omp |  5 +++++
 gcc/cp/semantics.cc  | 23 +++++++++++++++++------
 4 files changed, 43 insertions(+), 9 deletions(-)

diff --git a/gcc/c/ChangeLog.omp b/gcc/c/ChangeLog.omp
index a95b2adc8f8..4b8331c3744 100644
--- a/gcc/c/ChangeLog.omp
+++ b/gcc/c/ChangeLog.omp
@@ -1,3 +1,8 @@
+2021-08-19  Chung-Lin Tang  <cltang@codesourcery.com>
+
+	* c-typeck.cc (handle_omp_array_sections_1): Robustify non-contiguous
+	array check and reject non-DECL base-pointer cases as unsupported.
+
 2022-02-03  Kwok Cheung Yeung  <kcy@codesourcery.com>
 
 	* c-parser.ccc (c_parser_omp_clause_map): Update call to
diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index 7f466b858d9..3fea8185c0a 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -14186,14 +14186,27 @@ handle_omp_array_sections_1 (tree c, tree t, vec<tree> &types,
 	      if (d_length == NULL_TREE || !integer_onep (d_length))
 		{
 		  if (ort == C_ORT_ACC)
-		    non_contiguous = true;
-		  else
 		    {
+		      while (TREE_CODE (d) == TREE_LIST)
+			d = TREE_CHAIN (d);
+		      if (DECL_P (d))
+			{
+			  /* Note that OpenACC does accept these kinds of
+			     non-contiguous pointer based arrays.  */
+			  non_contiguous = true;
+			  break;
+			}
 		      error_at (OMP_CLAUSE_LOCATION (c),
-				"array section is not contiguous in %qs clause",
+				"base-pointer expression in %qs clause not "
+				"supported for non-contiguous arrays",
 				omp_clause_code_name[OMP_CLAUSE_CODE (c)]);
 		      return error_mark_node;
 		    }
+
+		  error_at (OMP_CLAUSE_LOCATION (c),
+			    "array section is not contiguous in %qs clause",
+			    omp_clause_code_name[OMP_CLAUSE_CODE (c)]);
+		  return error_mark_node;
 		}
 	    }
 	}
diff --git a/gcc/cp/ChangeLog.omp b/gcc/cp/ChangeLog.omp
index bfdc3be2c4e..71b0f57918f 100644
--- a/gcc/cp/ChangeLog.omp
+++ b/gcc/cp/ChangeLog.omp
@@ -1,3 +1,8 @@
+2021-08-19  Chung-Lin Tang  <cltang@codesourcery.com>
+
+	* semantics.cc (handle_omp_array_sections_1): Robustify non-contiguous
+	array check and reject non-DECL base-pointer cases as unsupported.
+
 2021-02-01  Chung-Lin Tang  <cltang@codesourcery.com>
 
 	* semantics.cc (finish_omp_clauses):  Adjust to allow duplicate
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 9c7258989f4..9b8d5ac2ce8 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -5824,9 +5824,7 @@ handle_omp_array_sections_1 (tree c, tree t, vec<tree> &types,
 	  return error_mark_node;
 	}
       /* If there is a pointer type anywhere but in the very first
-	 array-section-subscript, the array section could be non-contiguous.
-	 Note that OpenACC does accept these kinds of non-contiguous pointer
-	 based arrays.  */
+	 array-section-subscript, the array section could be non-contiguous.  */
       if (OMP_CLAUSE_CODE (c) != OMP_CLAUSE_AFFINITY
 	  && OMP_CLAUSE_CODE (c) != OMP_CLAUSE_DEPEND
 	  && TREE_CODE (TREE_OPERAND (t, 0)) == OMP_ARRAY_SECTION)
@@ -5840,14 +5838,27 @@ handle_omp_array_sections_1 (tree c, tree t, vec<tree> &types,
 	      if (d_length == NULL_TREE || !integer_onep (d_length))
 		{
 		  if (ort == C_ORT_ACC)
-		    non_contiguous = true;
-		  else
 		    {
+		      while (TREE_CODE (d) == TREE_LIST)
+			d = TREE_CHAIN (d);
+		      if (DECL_P (d))
+			{
+			  /* Note that OpenACC does accept these kinds of
+			     non-contiguous pointer based arrays.  */
+			  non_contiguous = true;
+			  break;
+			}
 		      error_at (OMP_CLAUSE_LOCATION (c),
-				"array section is not contiguous in %qs clause",
+				"base-pointer expression in %qs clause not "
+				"supported for non-contiguous arrays",
 				omp_clause_code_name[OMP_CLAUSE_CODE (c)]);
 		      return error_mark_node;
 		    }
+
+		  error_at (OMP_CLAUSE_LOCATION (c),
+			    "array section is not contiguous in %qs clause",
+			    omp_clause_code_name[OMP_CLAUSE_CODE (c)]);
+		  return error_mark_node;
 		}
 	    }
 	}