[gcc r16-7360] tree-optimization/114274 - avoid stray BLOCK refrence from CSWTCH vars

[Richard Biener]

https://gcc.gnu.org/g:48e114ee2a0d5b19796f4f03644d9d9925379e1f

commit r16-7360-g48e114ee2a0d5b19796f4f03644d9d9925379e1f
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Feb 6 09:26:37 2026 +0100

    tree-optimization/114274 - avoid stray BLOCK refrence from CSWTCH vars
    
    The following removes the location from CSWTCH variables which are
    DECL_IGNORED_P and have no DECL_CONTEXT.  The location is currently
    taken from the gswitch statement and thus includes a BLOCK reference
    which can eventually be elided and GCd, causing later ICEs when
    ICF decides to merge the variable with some other.
    
            PR tree-optimization/114274
            * tree-switch-conversion.cc (switch_conversion::build_one_array):
            Use UNKNOWN_LOCATION for the CSWTCH decl.

Diff:
---
 gcc/tree-switch-conversion.cc | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/gcc/tree-switch-conversion.cc b/gcc/tree-switch-conversion.cc
index cc2b0a5ec30c..5027ab559c0b 100644
--- a/gcc/tree-switch-conversion.cc
+++ b/gcc/tree-switch-conversion.cc
@@ -971,7 +971,6 @@ switch_conversion::build_one_array (int num, tree arr_index_type,
   tree name;
   gimple *load;
   gimple_stmt_iterator gsi = gsi_for_stmt (m_switch);
-  location_t loc = gimple_location (m_switch);
 
   gcc_assert (m_default_values[num]);
 
@@ -1030,7 +1029,7 @@ switch_conversion::build_one_array (int num, tree arr_index_type,
       TREE_CONSTANT (ctor) = true;
       TREE_STATIC (ctor) = true;
 
-      decl = build_decl (loc, VAR_DECL, NULL_TREE, array_type);
+      decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, NULL_TREE, array_type);
       TREE_STATIC (decl) = 1;
       DECL_INITIAL (decl) = ctor;