Nested functions are permitted for C but not C++ as extension.
They are also permitted for Fortran, which generates DECL_CONTEXT
== NAMESPACE_DECL for module variables.
That causes the gcc_assert (decl_function_context (decl) == info->context)
to fail in tree-nested.c's lookup_field_for_decl.
The call happens in convert_local_reference_stmt for:
2524 case GIMPLE_ASSIGN:
2525 if (gimple_clobber_p (stmt))
2528 if (DECL_P (lhs)
2529 && !use_pointer_in_frame (lhs)
2530 && lookup_field_for_decl (info, lhs, NO_INSERT))
The latter runs into the assert mentioned above. And the
'= {CLOBBER}' occurs in gfortran due to the intent(out).
As additional ingredient, a nested (internal) procedure involved,
obviously as otherwise tree-nested.c wouldn't be involved.
The patch fixes the assert and in terms of the assert it makes
sense, but I am not sure whether there are assumptions
elsewhere which are wrong for NAMESPACE_DECL.
OK for mainline? GCC 10?
Tobias
-----------------
Mentor Graphics (Deutschland) GmbH, Arnulfstrasse 201, 80634 München
Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, Frank
Thürauf
tree-nested: Update assert for Fortran module vars [PR97927]
gcc/ChangeLog:
PR fortran/97927
* tree-nested.c (lookup_field_for_decl): Also permit
that the var is a Fortran module var (= namespace context).
gcc/testsuite/ChangeLog:
PR fortran/97927
* gfortran.dg/module_variable_3.f90: New test.
gcc/testsuite/gfortran.dg/module_variable_3.f90 | 37 +++++++++++++++++++++++++
gcc/tree-nested.c | 3 +-
2 files changed, 39 insertions(+), 1 deletion(-)
diff --git a/gcc/testsuite/gfortran.dg/module_variable_3.f90 b/gcc/testsuite/gfortran.dg/module_variable_3.f90
new file mode 100644
index 00000000000..0dae6d5bdd5
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/module_variable_3.f90
@@ -0,0 +1,37 @@
+! { dg-do compile }
+! { dg-additional-options "-fdump-tree-original" }
+!
+! PR fortran/97927
+!
+! Did ICE due to the in tree-nested.c due to {clobber}
+!
+
+module mpi2
+ interface
+ subroutine MPI_Allreduce(i)
+ implicit none
+ INTEGER, OPTIONAL, INTENT(OUT) :: i
+ end subroutine MPI_Allreduce
+ end interface
+end module
+
+module modmpi
+ implicit none
+ integer ierror ! module variable = context NAMESPACE_DECL
+end module
+
+subroutine exxengy
+ use modmpi
+ use mpi2, only: mpi_allreduce
+ implicit none
+
+ ! intent(out) implies: ierror = {clobber}
+ call mpi_allreduce(ierror)
+
+contains
+ subroutine zrho2
+ return
+ end subroutine
+end subroutine
+
+! { dg-final { scan-tree-dump "ierror = {CLOBBER};" "original" } }
diff --git a/gcc/tree-nested.c b/gcc/tree-nested.c
index addd6eef9ab..cedeccac40b 100644
--- a/gcc/tree-nested.c
+++ b/gcc/tree-nested.c
@@ -382,7 +382,8 @@ static tree
lookup_field_for_decl (struct nesting_info *info, tree decl,
enum insert_option insert)
{
- gcc_checking_assert (decl_function_context (decl) == info->context);
+ gcc_checking_assert (decl_function_context (decl) == info->context
+ || TREE_CODE (DECL_CONTEXT (decl)) == NAMESPACE_DECL);
if (insert == NO_INSERT)
{
