https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113316
--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:c1680bd2df187e06089b06ffe211c4abe4c440b0 commit r14-7179-gc1680bd2df187e06089b06ffe211c4abe4c440b0 Author: Jakub Jelinek <ja...@redhat.com> Date: Fri Jan 12 11:19:08 2024 +0100 lower-bitint: Fix up handling of uninitialized large/huge _BitInt call arguments [PR113316] The code to assign large/huge _BitInt SSA_NAMEs to partitions intentionally ignores uninitialized SSA_NAMEs: /* Also ignore uninitialized uses. */ if (SSA_NAME_IS_DEFAULT_DEF (s) && (!SSA_NAME_VAR (s) || VAR_P (SSA_NAME_VAR (s)))) continue; because there is no need to store them into memory, all we need is when trying to extract some limb from them use uninitialized SSA_NAME for the limb. The following testcase shows this is a problem for call arguments though, for those we need to create replacement SSA_NAMEs which are loaded from the underlying variable. For uninitialized SSA_NAMEs because we didn't create underlying variable for them var_to_partition doesn't work, the following patch handles it by just creating an uninitialized replacement SSA_NAME. 2024-01-12 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/113316 * gimple-lower-bitint.cc (bitint_large_huge::lower_call): Handle uninitialized large/huge _BitInt arguments to calls. * gcc.dg/bitint-67.c: New test.