https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104689
--- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Szabolcs Nagy <n...@gcc.gnu.org>: https://gcc.gnu.org/g:0d344b557604e966dc7f91739881f03e1f221efd commit r13-753-g0d344b557604e966dc7f91739881f03e1f221efd Author: Szabolcs Nagy <szabolcs.n...@arm.com> Date: Thu Feb 10 17:42:56 2022 +0000 aarch64: Fix pac-ret with unusual dwarf in libgcc unwinder [PR104689] The RA_SIGN_STATE dwarf pseudo-register is normally only set using the DW_CFA_AARCH64_negate_ra_state (== DW_CFA_window_save) operation which toggles the return address signedness state (the default state is 0). (It may be set by remember/restore_state CFI too, those save/restore the state of all registers.) However RA_SIGN_STATE can be set directly via DW_CFA_val_expression too. GCC does not generate such CFI but some other compilers reportedly do. Note: the toggle operation must not be mixed with other dwarf register rule CFI within the same CIE and FDE. In libgcc we assume REG_UNSAVED means the RA_STATE is set using toggle operations, otherwise we assume its value is set by other CFI. libgcc/ChangeLog: PR target/104689 * config/aarch64/aarch64-unwind.h (aarch64_frob_update_context): Handle the !REG_UNSAVED case. * unwind-dw2.c (execute_cfa_program): Fail toggle if !REG_UNSAVED. gcc/testsuite/ChangeLog: PR target/104689 * gcc.target/aarch64/pr104689.c: New test.
