[gdb] Fix warning in foreach_arch selftests When running the selftests, I run into: ... $ gdb -q -batch -ex "maint selftest" ... Running selftest execute_cfa_program::aarch64:ilp32. warning: A handler for the OS ABI "GNU/Linux" is not built into this configuration of GDB. Attempting to continue with the default aarch64:ilp32 settings. ... and likewise for execute_cfa_program::i8086 and execute_cfa_program::ia64-elf32. The warning can easily be reproduced outside the selftests by doing: ... $ gdb -q -batch -ex "set arch aarch64:ilp32" ... and can be prevented by first doing "set osabi none". Fix the warning by setting osabi to none while doing selftests that iterate over all architectures. This causes a regression in the print_one_insn selftests for the ARC archictecture. The problem is pre-existing, and can be demonstrated (already without this patch) using: ... $ gdb -q -batch -ex "set osabi none" -ex "maint selftest print_one_insn::A6" Running selftest print_one_insn::A6. Self test failed: Cannot access memory at address 0x0 Ran 1 unit tests, 1 failed $ ... For ARC, we use the generic case in print_one_insn_test, containing this code: ... int kind = gdbarch_breakpoint_kind_from_pc (gdbarch, &pc); ... insn = gdbarch_sw_breakpoint_from_kind (gdbarch, kind, &bplen); ... The problem is that with osabi linux we trigger: ... static int arc_linux_breakpoint_kind_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr) { return trap_size; } ... but with osabi none: ... arc_breakpoint_kind_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr) { size_t length_with_limm = gdb_insn_length (gdbarch, *pcptr); ... which needs access to memory, and will consequently fail. Fix this in print_one_insn_test, in the default case, by iterating over supported osabi's to makes sure we trigger arc_linux_breakpoint_kind_from_pc which will give us a usable instruction to disassemble. Tested on x86_64-linux. --- gdb/disasm-selftests.c | 47 ++++++++++++++++++++++++++++++++++++++++++++--- gdb/osabi.c | 35 +++++++++++++++++++++++++++++------ gdb/osabi.h | 3 +++ gdb/selftest-arch.c | 1 + 4 files changed, 77 insertions(+), 9 deletions(-) diff --git a/gdb/disasm-selftests.c b/gdb/disasm-selftests.c index 928d26f7018..ccb60a0bc87 100644 --- a/gdb/disasm-selftests.c +++ b/gdb/disasm-selftests.c @@ -101,12 +101,53 @@ print_one_insn_test (struct gdbarch *gdbarch) { /* Test disassemble breakpoint instruction. */ CORE_ADDR pc = 0; - int kind = gdbarch_breakpoint_kind_from_pc (gdbarch, &pc); + int kind; int bplen; - insn = gdbarch_sw_breakpoint_from_kind (gdbarch, kind, &bplen); - len = bplen; + const char *arch = gdbarch_bfd_arch_info (gdbarch)->printable_name; + + enum gdb_osabi it; + bool found = false; + for (it = GDB_OSABI_UNKNOWN; it != GDB_OSABI_INVALID; + it = static_cast(static_cast(it) + 1)) + { + if (it == GDB_OSABI_UNKNOWN) + continue; + + struct gdbarch_info info; + info.bfd_arch_info = bfd_scan_arch (arch); + info.osabi = it; + + if (it != GDB_OSABI_NONE) + { + if (!has_gdb_osabi_handler (info)) + /* Unsupported. Skip to prevent warnings like: + A handler for the OS ABI is not built into this + configuration of GDB. Attempting to continue with the + default settings. */ + continue; + } + + gdbarch = gdbarch_find_by_info (info); + SELF_CHECK (gdbarch != NULL); + + try + { + kind = gdbarch_breakpoint_kind_from_pc (gdbarch, &pc); + insn = gdbarch_sw_breakpoint_from_kind (gdbarch, kind, &bplen); + } + catch (...) + { + continue; + } + found = true; + break; + } + + /* Assert that we have found an instruction to disassemble. */ + SELF_CHECK (found); + len = bplen; break; } } diff --git a/gdb/osabi.c b/gdb/osabi.c index bbd7635532f..d4cb7531c12 100644 --- a/gdb/osabi.c +++ b/gdb/osabi.c @@ -332,9 +332,10 @@ can_run_code_for (const struct bfd_arch_info *a, const struct bfd_arch_info *b) return (a == b || a->compatible (a, b) == a); } +/* Return OS ABI handler for INFO. */ -void -gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) +static struct gdb_osabi_handler * +gdbarch_osabi_handler (struct gdbarch_info info) { struct gdb_osabi_handler *handler; @@ -367,12 +368,28 @@ gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) ISA"). BFD doesn't normally consider 32-bit and 64-bit "compatible" so it doesn't succeed. */ if (can_run_code_for (info.bfd_arch_info, handler->arch_info)) - { - (*handler->init_osabi) (info, gdbarch); - return; - } + return handler; } + return nullptr; +} + +/* See osabi.h. */ + +bool +has_gdb_osabi_handler (struct gdbarch_info info) +{ + return gdbarch_osabi_handler (info) != nullptr; +} + +void +gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) +{ + struct gdb_osabi_handler *handler; + + gdb_assert (info.osabi != GDB_OSABI_UNKNOWN); + handler = gdbarch_osabi_handler (info); + if (info.osabi == GDB_OSABI_NONE) { /* Don't complain about no OSABI. Assume the user knows @@ -380,6 +397,12 @@ gdbarch_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) return; } + if (handler != nullptr) + { + (*handler->init_osabi) (info, gdbarch); + return; + } + warning ("A handler for the OS ABI \"%s\" is not built into this configuration\n" "of GDB. Attempting to continue with the default %s settings.\n", diff --git a/gdb/osabi.h b/gdb/osabi.h index be016732cbc..478a418aac2 100644 --- a/gdb/osabi.h +++ b/gdb/osabi.h @@ -74,6 +74,9 @@ enum gdb_osabi gdbarch_lookup_osabi (bfd *); string. */ enum gdb_osabi osabi_from_tdesc_string (const char *text); +/* Return true if there's an OS ABI handler for INFO. */ +bool has_gdb_osabi_handler (struct gdbarch_info info); + /* Initialize the gdbarch for the specified OS ABI variant. */ void gdbarch_init_osabi (struct gdbarch_info, struct gdbarch *); diff --git a/gdb/selftest-arch.c b/gdb/selftest-arch.c index f434da718d5..1fe0b2d59b4 100644 --- a/gdb/selftest-arch.c +++ b/gdb/selftest-arch.c @@ -68,6 +68,7 @@ foreach_arch_test_generator (const std::string &name, { struct gdbarch_info info; info.bfd_arch_info = bfd_scan_arch (arch); + info.osabi = GDB_OSABI_NONE; struct gdbarch *gdbarch = gdbarch_find_by_info (info); SELF_CHECK (gdbarch != NULL); function (gdbarch);