Neste breve tutorial, veremos as técnicas básicas para trabalhar com o GDB e também veremos como você pode (e deve) preparar arquivos para depuração do GDB.
O GDB é um depurador portátil de projeto GNU que roda em muitos sistemas UNIX e pode depurar muitas linguagens de programação, incluindo C, C ++, Free Pascal, FreeBASIC, Ada, Fortran, Python3, Swift, NASM e Rust.
Gdb
GDB? , UNIX- , . , VSCode ( Vim, NeoVim ( ), Emacs, Atom )
.cpp .
G++ -g ( , , GDB).
g++ -g file_name.cpp -o output_name
gdb output_name
Python- :
gdb -ex r --args python program_name.py <arguments>
Java jdb, c JDK.
, , OnlineGDB, debug, , .
GDB
GDB :
GNU gdb (Ubuntu 8.1-0ubuntu3) 8.1.0.20180409-git
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from 3_Hero's_Inventory.cpp...done.
, .
, (, ), cpp main(). c list b ( b main ):
(gdb) list
1 #include <iostream>
2 #include <string>
3
4 using namespace std;
5
6 int main(int argc, char *argv[])
7 {
8 // Hero's Inventory - ,
9
10 const int MAX_ITEMS = 10; // ,
(gdb) b 6
Breakpoint 1 at 0xcb5: file ./3_Hero's_Inventory.cpp, line 6.
r:
(gdb) r
Starting program: /home/username77177/gitprojects/learning/cpp/build_folder/3_Hero's_Inventory.cpp
Breakpoint 1, main (argc=1, argv=0x7fffffffdd18) at ./3_Hero's_Inventory.cpp:7
7 {
TUI, <Ctrl-x a>
, , f:
(gdb) f
#0 main (argc=1, argv=0x7fffffffdd18) at ./3_Hero's_Inventory.cpp:14
14 items[itemnum++] = "Sword";
, , n ( next):
(gdb) n
10 const int MAX_ITEMS = 10; // ,
GDB ( ) .
, , n , , " " (step-in) s:
(gdb) s
11 string items[MAX_ITEMS]; // c 10
( , step-in , )
() info locals:
(gdb) info locals
MAX_ITEMS = 10
items = {"", "", "", "", "", "", "", "", "", ""}
itemnum = 0
game = 247
, print _:
(gdb) print MAX_ITEMS
$1 = 10
set:
(gdb) set x = 77177
(gdb) print x
$1 = 77177
watch:
watch x
, (info registers):
(gdb) info registers
rax 0x7fffffffdc00 140737488346112
rbx 0xffffffffffffffff -1
rcx 0xa0 160
rdx 0x7fffffffdd28 140737488346408
rsi 0x7fffffffdd18 140737488346392
rdi 0x7fffffffdbf0 140737488346096
rbp 0x7fffffffdc30 0x7fffffffdc30
rsp 0x7fffffffdab0 0x7fffffffdab0
r8 0x7ffff782fd80 140737345944960
r9 0x0 0
r10 0x6 6
r11 0x7ffff7b77020 140737349382176
r12 0x7fffffffdc10 140737488346128
r13 0x7fffffffdd10 140737488346384
r14 0x0 0
r15 0x0 0
rip 0x555555554cfe 0x555555554cfe <main(int, char**)+100>
eflags 0x286 [ PF SF IF ]
cs 0x33 51
ss 0x2b 43
ds 0x0 0
es 0x0 0
fs 0x0 0
gs 0x0 0
breakpoints ( ) info breakpoints:
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y 0x0000555555554cb5 in main(int, char**)
at ./3_Hero's_Inventory.cpp:6
breakpoint already hit 1 time
2 breakpoint keep y 0x0000555555554cfe in main(int, char**)
at ./3_Hero's_Inventory.cpp:14
del breakpoint_num:
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y 0x0000555555554cb5 in main(int, char**)
at ./3_Hero's_Inventory.cpp:6
breakpoint already hit 1 time
2 breakpoint keep y 0x0000555555554cfe in main(int, char**)
at ./3_Hero's_Inventory.cpp:14
(gdb) del 1
(gdb) info breakpoints
Num Type Disp Enb Address What
2 breakpoint keep y 0x0000555555554cfe in main(int, char**)
at ./3_Hero's_Inventory.cpp:14
c:
(gdb) r
Starting program: /home/username77177/gitprojects/learning/cpp/build_folder/3_Hero's_Inventory.cpp
Breakpoint 3, main (argc=1, argv=0x7fffffffdd18) at ./3_Hero's_Inventory.cpp:7
7 {
(gdb) c
Continuing.
Breakpoint 2, main (argc=1, argv=0x7fffffffdd18) at ./3_Hero's_Inventory.cpp:14
14 items[itemnum++] = "Sword";
() call:
(gdb) call MyFunction()
Para continuar a execução da função e parar o programa quando ela (a função) terminar, você precisa escrever finishou fin:
(gdb) fin
Vale esclarecer que não pode ser usado finishno método principal.
Para concluir o programa, você precisa escrever kill:
(gdb) kill
Kill the program being debugged? (y or n) y
Você também pode escrever helpa qualquer momento e obter uma breve ajuda sobre como usar o depurador
(gdb) help
List of classes of commands:
aliases -- Aliases of other commands
breakpoints -- Making program stop at certain points
data -- Examining data
files -- Specifying and examining files
internals -- Maintenance commands
obscure -- Obscure features
running -- Running the program
stack -- Examining the stack
status -- Status inquiries
support -- Support facilities
tracepoints -- Tracing of program execution without stopping the program
user-defined -- User-defined commands
Type "help" followed by a class name for a list of commands in that class.
Type "help all" for the list of all commands.
Type "help" followed by command name for full documentation.
Type "apropos word" to search for commands related to "word".
Command name abbreviations are allowed if unambiguous.