https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100785
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-11 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:b6e4453172e6502318d31517b7d3771b157ae71a commit r11-8642-gb6e4453172e6502318d31517b7d3771b157ae71a Author: Jakub Jelinek <ja...@redhat.com> Date: Mon Jun 21 13:30:42 2021 +0200 inline-asm: Fix ICE with bitfields in "m" operands [PR100785] Bitfields, while they live in memory, aren't something inline-asm can easily operate on. For C and "=m" or "+m", we were diagnosing bitfields in the past in the FE, where c_mark_addressable had: case COMPONENT_REF: if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1))) { error ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1)); return false; } but that check got moved in GCC 6 to build_unary_op instead and now we emit an error during expansion and ICE afterwards (i.e. error-recovery). For "m" it used to be diagnosed in c_mark_addressable too, but since GCC 6 it is ice-on-invalid. For C++, this was never diagnosed in the FE, but used to be diagnosed in the gimplifier and/or during expansion before 4.8. The following patch does multiple things: 1) diagnoses it in the FEs 2) simplifies during expansion the inline asm if any errors have been reported (similarly how e.g. vregs pass if it detects errors on inline-asm either deletes them or simplifies to bare minimum - just labels), so that we don't have error-recovery ICEs there 2021-06-11 Jakub Jelinek <ja...@redhat.com> PR inline-asm/100785 gcc/ * cfgexpand.c (expand_asm_stmt): If errors are emitted, remove all inputs, outputs and clobbers from the asm and set template to "". gcc/c/ * c-typeck.c (c_mark_addressable): Diagnose trying to make bit-fields addressable. gcc/cp/ * typeck.c (cxx_mark_addressable): Diagnose trying to make bit-fields addressable. gcc/testsuite/ * c-c++-common/pr100785.c: New test. (cherry picked from commit 644c2cc5f2c09506a7bfef293a7f90efa8d7e5fa)