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numba之gdb调试
Python
2017-03-03 20:17:15
官网参考：http://numba.pydata.org/numba-doc/latest/user/troubleshoot.html#my-code-doesn-t-compile
文件：
# demo_gdb.py
from numba import njit, gdb
@njit(debug=True)
def foo(a):
b = a + 1
gdb() # instruct Numba to attach gdb at this location and pause execution
c = a * 2.34
d = (a, b, c)
print(a, b, c, d)
r= foo(123)
print(r)
shell
$ NUMBA_OPT=0 python demo_gdb.py
Attaching to PID: 27157
GNU gdb (GDB) Red Hat Enterprise Linux 8.0.1-36.el7
...
Attaching to process 27157
...
Reading symbols from ...done.
0x00007f0380c31550 in __nanosleep_nocancel () at ../sysdeps/unix/syscall-template.S:81
81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
Breakpoint 1 at 0x7f036ac388f0: file numba/_helperlib.c, line 1090.
Continuing.
Breakpoint 1, numba_gdb_breakpoint () at numba/_helperlib.c:1090
1090 }
(gdb) s
Single stepping until exit from function _ZN5numba7targets8gdb_hook8hook_gdb12$3clocals$3e8impl$242E5Tuple,
which has no line number information.
__main__::foo$241(long long) () at demo_gdb.py:7
7 c = a * 2.34
(gdb) l
2
3 @njit(debug=True)
4 def foo(a):
5 b = a + 1
6 gdb() # instruct Numba to attach gdb at this location and pause execution
7 c = a * 2.34
8 d = (a, b, c)
9 print(a, b, c, d)
10
11 r= foo(123)
(gdb) p a
$1 = 123
(gdb) p b
$2 = 124
(gdb) p c
$3 = 0
(gdb) n
8 d = (a, b, c)
(gdb) p c
$4 = 287.81999999999999
文件：
from numba import njit, gdb_init
import numpy as np
@njit(debug=True)
def foo(a, index):
gdb_init() # instruct Numba to attach gdb at this location, but not to pause execution
b = a + 1
c = a * 2.34
d = c[index] # access an address that is a) invalid b) out of the page
print(a, b, c, d)
bad_index = int(1e9) # this index is invalid
z = np.arange(10)
r = foo(z, bad_index)
print(r)
执行：
$ python demo_gdb_segfault.py
Attaching to PID: 5444
GNU gdb (GDB) Red Hat Enterprise Linux 8.0.1-36.el7
...
Attaching to process 5444
...
Reading symbols from ...done.
0x00007f8d8010a550 in __nanosleep_nocancel () at ../sysdeps/unix/syscall-template.S:81
81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
Breakpoint 1 at 0x7f8d6a1118f0: file numba/_helperlib.c, line 1090.
Continuing.
0x00007fa7b810a41f in __main__::foo$241(Array, long long) () at demo_gdb_segfault.py:9
9 d = c[index] # access an address that is a) invalid b) out of the page
(gdb) p index
$1 = 1000000000
(gdb) p c
$2 = "p\202\017\364\371U\000\000\000\000\000\000\000\000\000\000\n\000\000\000\000\000\000\000\b\000\000\000\000\000\000\000\240\202\017\364\371U\000\000\n\000\000\000\000\000\000\000\b\000\000\000\000\000\000"
(gdb) whatis c
type = {i8*, i8*, i64, i64, double*, [1 x i64], [1 x i64]}
(gdb) x /32xb c
0x7ffd56195068: 0x70 0x82 0x0f 0xf4 0xf9 0x55 0x00 0x00
0x7ffd56195070: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x7ffd56195078: 0x0a 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x7ffd56195080: 0x08 0x00 0x00 0x00 0x00 0x00 0x00 0x00
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