GCC produces corrupted debug info if the source code uses std::vector

[ilya-nozhkin]

Steps to reproduce:

1. Put this code into a new file named main.cpp:

#include <vector>

int main(int argc, char const *argv[]) {
  std::vector<int> int_vector;
  return 0;
}

2. Compile the source file with GCC 2021.09-eng009 or newer using the following command: arc-elf32-g++ -mcpu=hs4x -g -O0 -o main.elf main.cpp
3. Invoke objdump using this command: arc-elf32-objdump -W ./main.elf > objdump.txt

objdump will print the following warnings:

arc-elf32-objdump: Warning: There is a hole [0x23 - 0x35] in .debug_loc section.
arc-elf32-objdump: Warning: There is a hole [0x115f - 0x1171] in .debug_loc section.
arc-elf32-objdump: Warning: There is a hole [0x11fb - 0x120b] in .debug_loc section.
...
arc-elf32-objdump: Warning: There is a hole [0xc0a1 - 0xc0b5] in .debug_loc section.
arc-elf32-objdump: Warning: There is a hole [0xc7fb - 0xc80d] in .debug_loc section.
arc-elf32-objdump: Warning: There is a hole [0xd951 - 0xd963] in .debug_loc section.
arc-elf32-objdump: Warning: Corrupt offset (0x0000008b) in range entry 1
arc-elf32-objdump: Warning: Corrupt offset (0x0000009e) in range entry 2
arc-elf32-objdump: Warning: Corrupt offset (0x0000009e) in range entry 3
...
arc-elf32-objdump: Warning: Corrupt offset (0x00001f81) in range entry 561
arc-elf32-objdump: Warning: Corrupt offset (0x00001f8d) in range entry 562
arc-elf32-objdump: Warning: Corrupt offset (0x00001f99) in range entry 563

[claziss]

Simplified:

	.text
	.align 4
	.global	main
	.type	main, @function
main:
.LVL0:
.LVL1:
	.file 1 "main.c"
	.loc 1 89 7 is_stmt 0 view .LVU23
.LFE1009:
	.size	main, .-main

	.section	.debug_loclists,"",@progbits
	.4byte	@[email protected]_loc2	# Length of Location Lists
.Ldebug_loc2:
	.2byte	0x5	# DWARF version number
	.byte	0x4	# Address Size
	.byte	0	# Segment Size
	.4byte	0	# Offset Entry Count
.Ldebug_loc0:
.LVUS0:
	.uleb128 0	# View list begin (*.LVUS0)
	.uleb128 .LVU23	# View list end (*.LVUS0)
	.uleb128 .LVU23	# View list begin (*.LVUS0)
	.uleb128 0	# View list end (*.LVUS0)
.LLST0:
	.byte	0x6	# DW_LLE_base_address (*.LLST0)
	.4byte	@.LVL0	# Base address (*.LLST0)
	.byte	0x4	# DW_LLE_offset_pair (*.LLST0)
	.uleb128 .LVL0-.LVL0	# Location list begin address (*.LLST0)
	.uleb128 .LVL1-.LVL0	# Location list end address (*.LLST0)
	.uleb128 0x1	# Location expression size
	.byte	0x50	# DW_OP_reg0
	.byte	0x4	# DW_LLE_offset_pair (*.LLST0)
	.uleb128 .LVL1-.LVL0	# Location list begin address (*.LLST0)
	.uleb128 .LFE1009-.LVL0	# Location list end address (*.LLST0)
	.uleb128 0x4	# Location expression size
	.byte	0xa3	# DW_OP_entry_value
	.uleb128 0x1
	.byte	0x50	# DW_OP_reg0
	.byte	0x9f	# DW_OP_stack_value
	.byte	0	# DW_LLE_end_of_list (*.LLST0)
.Ldebug_loc3:

[claziss]

It looks related to this. By all means the error looks more estetical than functional, and it should not trigger any error during debugging.

[abrodkin]

@claziss do we need to do anything here or may just close it now?

[claziss]

Mainline issue. errors reduced to:

arc-elf32-objdump: Warning: There is a hole [0x849 - 0x85b] in .debug_loclists section.
arc-elf32-objdump: Warning: There is a hole [0x18bf - 0x18d1] in .debug_loclists section.

Closing this