From d25e3f4ed05c3a6c207263d7e532f829860b83f0 Mon Sep 17 00:00:00 2001 From: Tom de Vries Date: Wed, 20 Mar 2024 09:57:49 +0100 Subject: [PATCH 1/7] [gdb/symtab] Workaround PR gas/31115 On arm-linux, with gas 2.40, I run into: ... (gdb) x /i main+8^M 0x4e1 : vrhadd.u16 d14, d14, d31^M (gdb) FAIL: gdb.arch/pr25124.exp: disassemble thumb instruction (1st try) ... This is a regression due to PR gas/31115, which makes gas produce a low_pc with the thumb bit set (0x4d8 & 0x1): ... <1><24>: Abbrev Number: 2 (DW_TAG_subprogram) <25> DW_AT_name : main <29> DW_AT_external : 1 <29> DW_AT_type : <0x2f> <2a> DW_AT_low_pc : 0x4d9 <2e> DW_AT_high_pc : 12 ... The regression was introduced in 2.39, and is also present in 2.40 and 2.41, and hasn't been fixed yet. Work around this in read_func_scope, by using gdbarch_addr_bits_remove on low_pc and high_pc. Tested on arm-linux and x86_64-linux. PR tdep/31453 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31453 --- gdb/dwarf2/cu.c | 1 + gdb/dwarf2/cu.h | 1 + gdb/dwarf2/read.c | 22 ++++++++++++++++++++++ 3 files changed, 24 insertions(+) diff --git a/gdb/dwarf2/cu.c b/gdb/dwarf2/cu.c index f9b05dfc709..7f89500effd 100644 --- a/gdb/dwarf2/cu.c +++ b/gdb/dwarf2/cu.c @@ -42,6 +42,7 @@ dwarf2_cu::dwarf2_cu (dwarf2_per_cu_data *per_cu, producer_is_clang (false), producer_is_gas_lt_2_38 (false), producer_is_gas_2_39 (false), + producer_is_gas_ge_2_40 (false), processing_has_namespace_info (false), load_all_dies (false) { diff --git a/gdb/dwarf2/cu.h b/gdb/dwarf2/cu.h index ef8db480e3f..1b02f89ed2f 100644 --- a/gdb/dwarf2/cu.h +++ b/gdb/dwarf2/cu.h @@ -267,6 +267,7 @@ struct dwarf2_cu bool producer_is_clang : 1; bool producer_is_gas_lt_2_38 : 1; bool producer_is_gas_2_39 : 1; + bool producer_is_gas_ge_2_40 : 1; /* When true, the file that we're processing is known to have debugging info for C++ namespaces. GCC 3.3.x did not produce diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index a4f982962ae..8f2d7a34aef 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -148,6 +148,7 @@ static int dwarf2_loclist_block_index; static int ada_block_index; static bool producer_is_gas_lt_2_38 (struct dwarf2_cu *cu); +static bool producer_is_gas_ge_2_39 (struct dwarf2_cu *cu); /* Size of .debug_loclists section header for 32-bit DWARF format. */ #define LOCLIST_HEADER_SIZE32 12 @@ -10223,6 +10224,15 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu) lowpc = per_objfile->relocate (unrel_low); highpc = per_objfile->relocate (unrel_high); + if (gdbarch_bfd_arch_info (gdbarch)->arch == bfd_arch_arm + && producer_is_gas_ge_2_39 (cu)) + { + /* Gas version 2.39 produces DWARF for a Thumb subprogram with a low_pc + attribute with the thumb bit set (PR gas/31115). Work around this. */ + lowpc = gdbarch_addr_bits_remove (gdbarch, lowpc); + highpc = gdbarch_addr_bits_remove (gdbarch, highpc); + } + /* If we have any template arguments, then we must allocate a different sort of symbol. */ for (child_die = die->child; child_die; child_die = child_die->sibling) @@ -11507,6 +11517,7 @@ check_producer (struct dwarf2_cu *cu) { cu->producer_is_gas_lt_2_38 = major < 2 || (major == 2 && minor < 38); cu->producer_is_gas_2_39 = major == 2 && minor == 39; + cu->producer_is_gas_ge_2_40 = major > 2 || (major == 2 && minor >= 40); } else { @@ -11561,6 +11572,17 @@ producer_is_gas_2_39 (struct dwarf2_cu *cu) return cu->producer_is_gas_2_39; } +/* Return true if CU is produced by GAS 2.39 or later. */ + +static bool +producer_is_gas_ge_2_39 (struct dwarf2_cu *cu) +{ + if (!cu->checked_producer) + check_producer (cu); + + return cu->producer_is_gas_2_39 || cu->producer_is_gas_ge_2_40; +} + /* Return the accessibility of DIE, as given by DW_AT_accessibility. If that attribute is not available, return the appropriate default. */ base-commit: c79ecacd3f75cfb0ec1a3afc49ca3f30b1759009 -- 2.35.3