From FEDORA_PATCHES Mon Sep 17 00:00:00 2001 From: Keith Seitz Date: Wed, 26 Jan 2022 08:56:18 -0800 Subject: gdb-rhbz2042257-ftbs-updates.patch MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ;; Fix build problems. ;; (RHBZ 2042257, Keith Seitz, Andrew Burgess) 1) Reference array of structs instead of first member during memcpy aarch64-tdep.c defines the following macro: do \ { \ unsigned int mem_len = LENGTH; \ if (mem_len) \ { \ MEMS = XNEWVEC (struct aarch64_mem_r, mem_len); \ memcpy(&MEMS->len, &RECORD_BUF[0], \ sizeof(struct aarch64_mem_r) * LENGTH); \ } \ } \ while (0) This is simlpy allocating a new array and copying it. However, for the destination address, it is actually copying into the first member of the first element of the array (`&MEMS->len"). This elicits a warning with GCC 12: ../../binutils-gdb/gdb/aarch64-tdep.c: In function ‘int aarch64_process_record(gdbarch*, regcache*, CORE_ADDR)’: ../../binutils-gdb/gdb/aarch64-tdep.c:3711:23: error: writing 16 bytes into a region of size 8 [-Werror=stringop-overflow=] 3711 | memcpy(&MEMS->len, &RECORD_BUF[0], \ | ^ ../../binutils-gdb/gdb/aarch64-tdep.c:4394:3: note: in expansion of macro ‘MEM_ALLOC’ 4394 | MEM_ALLOC (aarch64_insn_r->aarch64_mems, aarch64_insn_r->mem_rec_count, | ^~~~~~~~~ ../../binutils-gdb/gdb/aarch64-tdep.c:3721:12: note: destination object ‘aarch64_mem_r::len’ of size 8 3721 | uint64_t len; /* Record length. */ | ^~~ The simple fix is to reference the array, `MEMS' as the destination of the copy. Tested by rebuilding. 2) Fix build with current GCC: EL_EXPLICIT(location) always non-NULL Compiling GDB with current GCC (1b4a63593b) runs into this: src/gdb/location.c: In function 'int event_location_empty_p(const event_location*)': src/gdb/location.c:963:38: error: the address of 'event_location::::explicit_loc' will never be NULL [-Werror=address] 963 | return (EL_EXPLICIT (location) == NULL | ^ src/gdb/location.c:57:30: note: 'event_location::::explicit_loc' declared here 57 | struct explicit_location explicit_loc; | ^~~~~~~~~~~~ GCC is right, EL_EXPLICIT is defined as returning the address of an union field: /* An explicit location. */ struct explicit_location explicit_loc; #define EL_EXPLICIT(P) (&((P)->u.explicit_loc)) and thus must always be non-NULL. diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c --- a/gdb/aarch64-tdep.c +++ b/gdb/aarch64-tdep.c @@ -3666,7 +3666,7 @@ When on, AArch64 specific debugging is enabled."), if (mem_len) \ { \ MEMS = XNEWVEC (struct aarch64_mem_r, mem_len); \ - memcpy(&MEMS->len, &RECORD_BUF[0], \ + memcpy(MEMS, &RECORD_BUF[0], \ sizeof(struct aarch64_mem_r) * LENGTH); \ } \ } \ diff --git a/gdb/location.c b/gdb/location.c --- a/gdb/location.c +++ b/gdb/location.c @@ -960,12 +960,11 @@ event_location_empty_p (const struct event_location *location) return 0; case EXPLICIT_LOCATION: - return (EL_EXPLICIT (location) == NULL - || (EL_EXPLICIT (location)->source_filename == NULL - && EL_EXPLICIT (location)->function_name == NULL - && EL_EXPLICIT (location)->label_name == NULL - && (EL_EXPLICIT (location)->line_offset.sign - == LINE_OFFSET_UNKNOWN))); + return (EL_EXPLICIT (location)->source_filename == NULL + && EL_EXPLICIT (location)->function_name == NULL + && EL_EXPLICIT (location)->label_name == NULL + && (EL_EXPLICIT (location)->line_offset.sign + == LINE_OFFSET_UNKNOWN)); case PROBE_LOCATION: return EL_PROBE (location) == NULL;