https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101118
--- Comment #18 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Iain D Sandoe <ia...@gcc.gnu.org>: https://gcc.gnu.org/g:b7e75cdb218f25708b8b1aa3f4b138d88187491f commit r12-9501-gb7e75cdb218f25708b8b1aa3f4b138d88187491f Author: Iain Sandoe <i...@sandoe.co.uk> Date: Thu Mar 30 13:14:23 2023 +0530 c++,coroutines: Stabilize names of promoted slot vars [PR101118]. When we need to 'promote' a value (i.e. store it in the coroutine frame) it is given a frame entry name. This was based on the DECL_UID for slot vars. However, when LTO is used, the names from multiple TUs become visible at the same time, and the DECL_UIDs usually differ between units. This leads to a "ODR mismatch" warning for the frame type. The fix here is to use the current promoted temporaries count to produce the name, this is stable between TUs and computed per coroutine. Signed-off-by: Iain Sandoe <i...@sandoe.co.uk> PR c++/101118 gcc/cp/ChangeLog: * coroutines.cc (flatten_await_stmt): Use the current count of promoted temporaries to build a unique name for the frame entries. (cherry picked from commit fc4cde2e6aa4d6ebdf7f70b7b4359fb59a1915ae)