[PATCH,fortran] Fix Bug 101760 - [13/14/15/16 Regression] ICE in make_ssa_name_fn ...

From 55be263a7ce0857276e5b26d5bdc1498b8bdc7ff Mon Sep 17 00:00:00 2001
From: Christopher Albert <[email protected]>
Date: Sat, 11 Apr 2026 15:13:19 +0200
Subject: [PATCH] fortran: Fix ICE in remap_type with deferred-length character
 in OMP target [PR101760, PR102314]

For deferred-length character types such as character(:), allocatable,
TYPE_SIZE and TYPE_SIZE_UNIT contain SAVE_EXPRs wrapping the string
length variable (created by variable_size in finalize_type_size).
In gfc_omp_finish_clause, when computing OMP_CLAUSE_SIZE for implicitly
mapped variables, the code previously used TYPE_SIZE_UNIT directly.
Gimplifying this shared SAVE_EXPR resolves it in place, embedding a
gimple temporary into the type's size expression.  When the enclosing
function is later inlined, remap_type_1 walks TYPE_SIZE and encounters
the stale temporary as an unmappable SSA name, causing an ICE in
make_ssa_name_fn.

Fix by computing the clause size from the array domain bounds and
element size rather than using the type's SAVE_EXPR directly, so
that the type's size expressions remain untouched.

	PR fortran/101760
	PR fortran/102314

gcc/fortran/ChangeLog:

	* trans-openmp.cc (gfc_omp_finish_clause): Compute OMP_CLAUSE_SIZE
	from the array domain bounds and element size for VLA types instead
	of using TYPE_SIZE_UNIT directly, to avoid corrupting the type.

gcc/testsuite/ChangeLog:

	* gfortran.dg/gomp/pr101760.f90: New test.
	* gfortran.dg/gomp/pr102314.f90: New test.

Signed-off-by: Christopher Albert <[email protected]>
---
 gcc/fortran/trans-openmp.cc                 | 36 +++++++++++++++++++--
 gcc/testsuite/gfortran.dg/gomp/pr101760.f90 | 14 ++++++++
 gcc/testsuite/gfortran.dg/gomp/pr102314.f90 | 19 +++++++++++
 3 files changed, 66 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/gfortran.dg/gomp/pr101760.f90
 create mode 100644 gcc/testsuite/gfortran.dg/gomp/pr102314.f90

diff --git a/gcc/fortran/trans-openmp.cc b/gcc/fortran/trans-openmp.cc
index 230395f9d2c..538ba045530 100644
--- a/gcc/fortran/trans-openmp.cc
+++ b/gcc/fortran/trans-openmp.cc
@@ -1839,9 +1839,39 @@ gfc_omp_finish_clause (tree c, gimple_seq *pre_p, bool openacc)
   else
     {
       if (OMP_CLAUSE_SIZE (c) == NULL_TREE)
-	OMP_CLAUSE_SIZE (c)
-	  = DECL_P (decl) ? DECL_SIZE_UNIT (decl)
-			  : TYPE_SIZE_UNIT (TREE_TYPE (decl));
+	{
+	  if (DECL_P (decl))
+	    OMP_CLAUSE_SIZE (c) = DECL_SIZE_UNIT (decl);
+	  else
+	    {
+	      tree type = TREE_TYPE (decl);
+	      tree size = TYPE_SIZE_UNIT (type);
+	      /* For variable-length character types, TYPE_SIZE_UNIT is a
+		 SAVE_EXPR.  Gimplifying the SAVE_EXPR (here or elsewhere)
+		 resolves it in place, embedding a gimple temporary that
+		 later causes an ICE in remap_type during inlining because
+		 the temporary is not in scope (PR101760, PR102314).
+		 Compute the size from the array domain and element size
+		 to decouple completely from the type's SAVE_EXPRs.  */
+	      if (size
+		  && TREE_CODE (type) == ARRAY_TYPE
+		  && TYPE_DOMAIN (type)
+		  && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
+		  && !TREE_CONSTANT (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
+		{
+		  tree len = TYPE_MAX_VALUE (TYPE_DOMAIN (type));
+		  tree lb = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
+		  tree eltsz = TYPE_SIZE_UNIT (TREE_TYPE (type));
+		  len = fold_build2 (MINUS_EXPR, TREE_TYPE (len), len, lb);
+		  len = fold_build2 (PLUS_EXPR, TREE_TYPE (len), len,
+				     build_one_cst (TREE_TYPE (len)));
+		  size = fold_build2 (MULT_EXPR, sizetype,
+				      fold_convert (sizetype, len),
+				      fold_convert (sizetype, eltsz));
+		}
+	      OMP_CLAUSE_SIZE (c) = size;
+	    }
+	}
 
       tree type = TREE_TYPE (decl);
       if (POINTER_TYPE_P (type) && POINTER_TYPE_P (TREE_TYPE (type)))
diff --git a/gcc/testsuite/gfortran.dg/gomp/pr101760.f90 b/gcc/testsuite/gfortran.dg/gomp/pr101760.f90
new file mode 100644
index 00000000000..ab7bf515a8c
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/gomp/pr101760.f90
@@ -0,0 +1,14 @@
+! PR fortran/101760
+! { dg-do compile }
+! { dg-options "-fopenmp -O1" }
+
+! Verify that deferred-length character variables with the TARGET attribute
+! in OpenMP target regions do not ICE during inlining.
+
+program p
+   character(:), allocatable, target :: x
+   logical :: l
+   !$omp target map(from: l)
+   l = allocated (x)
+   !$omp end target
+end
diff --git a/gcc/testsuite/gfortran.dg/gomp/pr102314.f90 b/gcc/testsuite/gfortran.dg/gomp/pr102314.f90
new file mode 100644
index 00000000000..6e8a45487f3
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/gomp/pr102314.f90
@@ -0,0 +1,19 @@
+! PR fortran/102314
+! { dg-do compile }
+! { dg-options "-fopenmp -O2" }
+
+! Verify that deferred-length character allocatables used inside
+! OpenMP target regions do not ICE during SSA verification or inlining.
+
+program p
+   character(:), allocatable :: y
+   call s(y)
+   !$omp target
+   y = 'abc'
+   !$omp end target
+contains
+   subroutine s(x)
+      character(:), allocatable :: x
+      x = '123'
+   end
+end
-- 
2.53.0