Index: libcxx/utils/gdb/libcxx/printers.py =================================================================== --- libcxx/utils/gdb/libcxx/printers.py +++ libcxx/utils/gdb/libcxx/printers.py @@ -27,6 +27,7 @@ _long_int_type = gdb.lookup_type("unsigned long long") +_libcpp_big_endian = False def addr_as_long(addr): return int(addr.cast(_long_int_type)) @@ -195,19 +196,14 @@ field = short_field.type.fields()[1].type.fields()[0] libcpp_abi_alternate_string_layout = field.name and "__padding" in field.name - # Strictly, this only tells us the current mode, not how libcxx was - # compiled. - libcpp_big_endian = "big endian" in gdb.execute("show endian", - to_string=True) - # This logical structure closely follows the original code (which is clearer # in C++). Keep them parallel to make them easier to compare. if libcpp_abi_alternate_string_layout: - if libcpp_big_endian: + if _libcpp_big_endian: return short_size >> 1 else: return short_size - elif libcpp_big_endian: + elif _libcpp_big_endian: return short_size else: return short_size >> 1 @@ -969,6 +965,14 @@ # certain pathological cases. Limit our pretty printers to the progspace. def _register_libcxx_printers(event): progspace = event.new_objfile.progspace + # It would be ideal to get the endianness at print time, but + # gdb.execute clears gdb's internal wrap buffer, removing any values + # already generated as part of a larger data structure, and there is + # no python api to get the endianness. Mixed-endianness debugging + # rare enough that this workaround should be adequate. + _libcpp_big_endian = "big endian" in gdb.execute("show endian", + to_string=True) + if not getattr(progspace, _libcxx_printer_name, False): print("Loading libc++ pretty-printers.") gdb.printing.register_pretty_printer(