https://gcc.gnu.org/g:68d3f1e2c20efe07f99de3720d1732c4b987ff22
commit r17-1397-g68d3f1e2c20efe07f99de3720d1732c4b987ff22 Author: Martin Uecker <[email protected]> Date: Sat Jun 6 15:08:19 2026 +0200 c: fix wrong encoding for zero-sized arrays [PR125618] This reverts one change from 106970adca69c9c577e6c75f4e69a08cd9ea2df0 that replaced build_range_type with build_index_type. In the function complete_array_type this breaks zero-sized arrays created from an empty initializer which there are represented using the C++ FE way [0, -1] causing issues on 32 bit architectures. After this partial revert this representation remains inconsistent to the usual C FE representation [0, NULL_TREE] (as before by change). PR c/125618 gcc/c-family/ChangeLog: * c-common.cc (complete_array_type): Change back to using build_range_type. Diff: --- gcc/c-family/c-common.cc | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc index ba72278bd522..a16288f4441c 100644 --- a/gcc/c-family/c-common.cc +++ b/gcc/c-family/c-common.cc @@ -7457,7 +7457,9 @@ complete_array_type (tree *ptype, tree initial_value, bool do_default) TYPE_LANG_FLAG_? bits that the front end may have set. */ main_type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type)); TREE_TYPE (main_type) = unqual_elt; - TYPE_DOMAIN (main_type) = build_index_type (maxindex); + TYPE_DOMAIN (main_type) + = build_range_type (TREE_TYPE (maxindex), + build_int_cst (TREE_TYPE (maxindex), 0), maxindex); TYPE_TYPELESS_STORAGE (main_type) = TYPE_TYPELESS_STORAGE (type); layout_type (main_type);
