https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118771
--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Andrew Pinski <pins...@gcc.gnu.org>: https://gcc.gnu.org/g:ea4278b1ced4a4c982678094e98ef3efd844917a commit r15-7419-gea4278b1ced4a4c982678094e98ef3efd844917a Author: Andrew Pinski <quic_apin...@quicinc.com> Date: Thu Feb 6 15:59:41 2025 -0800 aarch64: Fix bootstrap with --enable-checking=release [PR118771] With release checking we get an uninitialization warning inside aarch64_split_move because of jump threading for the case of `npieces==0` but `npieces` is never 0 (but there is no way the compiler can know that. So this fixes the issue by adding a `gcc_assert` to the function which asserts that `npieces > 0` and fixes the uninitialization warning. Bootstrapped and tested on aarch64-linux-gnu (with and without --enable-checking=release). The warning: aarch64.cc: In function 'void aarch64_split_move(rtx, rtx, machine_mode)': aarch64.cc:3418:31: error: '*(rtx_def**)((char*)&dst_pieces + offsetof(auto_vec<rtx_def*, 4>,auto_vec<rtx_def*, 4>::m_data[0]))' may be used uninitialized [-Werror=maybe-uninitialized] 3418 | if (reg_overlap_mentioned_p (dst_pieces[0], src)) | ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~ aarch64.cc:3408:20: note: 'dst_pieces' declared here 3408 | auto_vec<rtx, 4> dst_pieces, src_pieces; | ^~~~~~~~~~ PR target/118771 gcc/ChangeLog: * config/aarch64/aarch64.cc (aarch64_split_move): Assert that npieces is greater than 0. Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
