forked from Imagelibrary/binutils-gdb
2ef34d11f6
This is a backport of33b4777ca1btrace, frame: fix crash in get_frame_typea038fa3e14stack: check frame_unwind_caller_id2f3ef606b9frame: add skip_tailcall_frames In skip_artificial_frames we repeatedly call get_prev_frame_always until we get a non-inline and non-tailcall frame assuming that there must be such a frame eventually. For record targets, however, we may have a frame chain that consists only of artificial frames. This leads to a crash in get_frame_type when dereferencing a NULL frame pointer. Change skip_artificial_frames and skip_tailcall_frames to return NULL in such a case and modify each caller to cope with a NULL return. In frame_unwind_caller_pc and frame_unwind_caller_arch, we simply assert that the returned value is not NULL. Their caller was supposed to check frame_unwind_caller_id before calling those functions. In other cases, we thrown an error. In infcmd further move the skip_tailcall_frames call to the forward-stepping case since we don't need a frame for reverse execution and we don't want to fail because of that. Reverse-finish does make sense for a tailcall frame. gdb/ * frame.h (skip_tailcall_frames): New. * infcmd.c (finish_command): Call skip_tailcall_frames. * frame.c (skip_artificial_frames): Return NULL if only artificial frames are found. Update comment. (frame_pop): Call skip_tailcall_frames. (frame_unwind_caller_id): Handle NULL return. (frame_unwind_caller_pc, frame_unwind_caller_arch): Assert that skip_artificial_frames does not return NULL. (frame_pop): Add an error if only tailcall frames are found. * infcmd.c (finish_command): Move skip_tailcall_frames call into forward- execution case. Add an error if only tailcall frames are found. * stack.c (frame_info): Check frame_unwind_caller_id. testsuite/ * gdb.btrace/tailcall-only.exp: New. * gdb.btrace/tailcall-only.c: New. * gdb.btrace/x86_64-tailcall-only.S: New. * gdb.btrace/i686-tailcall-only.S: New.