{"id":4278,"date":"2020-04-14T11:03:05","date_gmt":"2020-04-14T03:03:05","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=4278"},"modified":"2020-04-14T11:03:05","modified_gmt":"2020-04-14T03:03:05","slug":"gdb%e7%9a%84%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/4278","title":{"rendered":"GDB\u7684\u4f7f\u7528"},"content":{"rendered":"
\n

\u7f16\u8bd1\u9009\u9879<\/span><\/h2>\n<\/div>\n

\u8981\u8c03\u8bd5C\/C++<\/code>\u7684\u7a0b\u5e8f\uff0c\u5728\u7f16\u8bd1\u65f6\uff0c\u8981\u628a\u8c03\u8bd5\u4fe1\u606f\u52a0\u5230\u53ef\u6267\u884c\u6587\u4ef6\u4e2d\u3002\u7f16\u8bd1\u5668(cc\/gcc\/g++)\u6dfb\u52a0-g<\/code>\u53c2\u6570\u3002<\/p>\n

\u6bd4\u5982\uff1ag++ -g hello.cpp -o hello<\/p>\n

\n

\u542f\u52a8gdb<\/h3>\n<\/div>\n

1) gdb -p \u8fdb\u7a0bID<\/p>\n

\u8c03\u8bd5\u6b63\u5728\u8fd0\u884c\u7684\u7a0b\u5e8f, \u627e\u5230\u8fdb\u7a0bID\u4e4b\u540e, gdb -p\u8fc7\u53bb\u5c31\u53ef\u4ee5\r\n<\/code><\/pre>\n
2) gdb \u4e8c\u8fdb\u5236\u6587\u4ef6\u540d<\/p>\n
\u76f4\u63a5\u7528gdb\u542f\u52a8\u7a0b\u5e8f, \u5982\u679c\u7a0b\u5e8f\u505a\u8fc7fork\u4e4b\u7c7b\u7684, \u9700\u8981\u8bbe\u7f6egdb\u53c2\u6570`set<\/span> follow-fork-mode<\/span> child<\/span>`\r\n<\/span><\/code><\/pre>\n
3) gdb \u4e8c\u8fdb\u5236\u6587\u4ef6\u540d coredump<\/p>\n
\u8c03\u8bd5dump<\/span>\u6587\u4ef6\r\n<\/code><\/pre>\n
\n
\u5e38\u7528\u7684\u8c03\u8bd5\u547d\u4ee4<\/h3>\n<\/div>\n
\n
\u8bbe\u7f6e\u65ad\u70b9\uff1a<\/h4>\n<\/div>\n
1) b \u6587\u4ef6\u540d:\u884c\u53f7<\/p>\n
   (gdb) b main.cpp:10\r\n<\/code><\/pre>\n
2) b \u51fd\u6570\u540d<\/p>\n
```gdb\r\n(gdb) b ProcessMessage\r\n(gdb) b Server::<\/span>Loop<\/span>\r\n```\r\n<\/code><\/pre>\n
\n
\u6761\u4ef6\u65ad\u70b9:<\/h4>\n<\/div>\n
cond(ition) bnum expression<\/p>\n
\u4f8b\u5982\u60f3\u8981\u5728a\u53d8\u91cf\u7b49\u4e8e1\u7684\u65f6\u5019, \u8fdb\u5165\u65ad\u70b910, \u90a3\u4e48\u5c31\u662f:<\/p>\n
   (gdb)cond 10 a == 1\r\n<\/code><\/pre>\n
\n
\u6570\u636e\u65ad\u70b9<\/h4>\n<\/div>\n
watch \u53d8\u91cf<\/p>\n
\u4f8b\u5982\u6709\u4e00\u4e2a\u53d8\u91cfa, \u6211\u60f3\u77e5\u9053\u4ed6\u5728\u90a3\u91cc\u88ab\u6539\u53d8\u4e86<\/p>\n
   (gdb)watch a\r\n<\/code><\/pre>\n
\u4e5f\u6709\u53ef\u80fd\u662f\u7a0b\u5e8f\u5199\u8d8a\u754c\u5bfc\u81f4\u4e86a\u53d8\u91cf\u88ab\u6539\u53d8(a\u7684\u7c7b\u578b\u4e3aint)<\/p>\n
   (gdb)watch *(int*)&a\r\n<\/code><\/pre>\n
\n
\u542f\u7528\u5173\u95ed\u65ad\u70b9<\/h4>\n<\/div>\n
info b\u53ef\u4ee5\u770b\u5230\u6240\u6709\u7684\u65ad\u70b9\u4fe1\u606f(\u72b6\u6001)<\/p>\n
enable \u65ad\u70b9\u7f16\u53f7, \u542f\u7528\u65ad\u70b9<\/p>\n
disable \u65ad\u70b9\u7f16\u53f7, \u5173\u95ed\u65ad\u70b9<\/p>\n
delete \u65ad\u70b9\u7f16\u53f7, \u5220\u9664\u65ad\u70b9<\/p>\n
   (gdb) info b\r\n   (gdb) enable 1\r\n   (gdb) disable 2\r\n   (gdb) delete 3\r\n<\/code><\/pre>\n
\n
\u6062\u590d\u7a0b\u5e8f\u8fd0\u884c\u548c\u5355\u6b65\u8c03\u8bd5\uff1a<\/h4>\n<\/div>\n
step\/s : \u5355\u6b65\u8ddf\u8e2a\uff0c\u5982\u679c\u6709\u51fd\u6570\u8c03\u7528\uff0c\u4f1a\u8fdb\u5165\u8be5\u51fd\u6570<\/p>\n
next\/n : \u5355\u6b65\u8ddf\u8e2a\uff0c\u5982\u679c\u6709\u51fd\u6570\u8c03\u7528\uff0c\u4e0d\u4f1a\u8fdb\u5165\u8be5\u51fd\u6570<\/p>\n
finish : \u8fd0\u884c\u7a0b\u5e8f\uff0c\u77e5\u9053\u5f53\u524d\u51fd\u6570\u5b8c\u6210\u8fd4\u56de<\/p>\n
continue\/c : \u7ee7\u7eed\u8fd0\u884c<\/p>\n
run\/r : \u8fd0\u884c\u7a0b\u5e8f<\/p>\n
\n
\u5176\u4ed6\u5e38\u7528\u547d\u4ee4\uff1a<\/h4>\n<\/div>\n
p i : \u6253\u5370\u53d8\u91cfi\u7684\u503c\uff0cp\u662fprint\u547d\u4ee4\u7684\u7f29\u5199<\/p>\n
x : \u7528\u6765\u67e5\u770b\u4e00\u6bb5\u5185\u5b58\u7684\u6307\u4ee4, x\/nfu, n\u662f\u4e2a\u6570, f\u662fformat, u\u662f\u5355\u4f4d(b,h,w,g), \u5177\u4f53\u9700\u8981\u770bgdb\u624b\u518c<\/p>\n
bt : \u67e5\u770b\u51fd\u6570\u5806\u6808<\/p>\n
f: \u5207\u6362\u51fd\u6570\u6808, \u6bd4\u5982f 1, f 10<\/p>\n
frame \u6808\u5e27\u53f7 : \u6253\u5370\u6808\u5e27<\/p>\n
list : \u663e\u793a\u7a0b\u5e8f\u4e2d\u7684\u4ee3\u7801, \u53ef\u4ee5\u901a\u8fc7+-\u6765\u63a7\u5236\u5411\u4e0a\u7ffb\u8fd8\u662f\u5411\u4e0b\u7ffb<\/p>\n
quit \uff1a\u9000\u51fagdb<\/p>\n
\n
\u8bbe\u7f6e\u53d8\u91cf\u7684\u503c<\/h4>\n<\/div>\n
\u6709\u65f6\u5019\u9700\u8981\u5728\u8fd0\u884c\u7684\u65f6\u5019\u4fee\u6539\u53d8\u91cf\u7684\u503c, \u53ef\u4ee5\u901a\u8fc7set\u6765\u505a<\/p>\n
   (gdb) set a = 10\r\n   (gdb) set *(int*)0x8048a51 = 100\r\n<\/code><\/pre>\n
\n
coredump\u7b49\u95ee\u9898\u7684\u5b9a\u4f4d\u53ca\u89e3\u51b3<\/h3>\n<\/div>\n
\n
gdb coredump\u5e94\u7528\u7a0b\u5e8f coredump\u6587\u4ef6<\/h4>\n<\/div>\n
\n
\u901a\u8fc7\u4ee5\u4e0b\u547d\u4ee4\u8c03\u8bd5<\/h4>\n<\/div>\n
info threads \u663e\u793a\u6240\u6709\u7ebf\u7a0b<\/p>\n
bt \u663e\u793a\u7ebf\u7a0b\u5806\u6808\u4fe1\u606f<\/p>\n
thread thread_num \u5207\u6362\u7ebf\u7a0b<\/p>\n
frame num \u5207\u6362\u6808<\/p>\n
\n
gdb\u5e38\u89c1\u95ee\u9898<\/h3>\n<\/div>\n
1) C++11\u7684auto\u53d8\u91cf\u6253\u5370<\/p>\n
auto<\/span>\u53d8\u91cf\u53ef\u80fd\u4e0d\u80fd\u6b63\u5e38\u6253\u5370\u671f\u6570\u636e\u548c\u7c7b\u578b\r\n<\/code><\/pre>\n
2) \u6355\u83b7\u4fe1\u53f7<\/p>\n
\u53d1\u9001\u7ed9\u7a0b\u5e8f\u7684\u4fe1\u53f7, \u53ef\u80fd\u4f1a\u88abgdb\u6355\u83b7, \u800c\u4e0d\u662f\u88ab\u7a0b\u5e8f\u5904\u7406, \u8fd9\u662f\u6b63\u5e38\u73b0\u8c61 3) \u53d8\u91cf\u503c\u9519\u8bef<\/p>\n
gdb\u6709\u65f6\u5019\u4f1a\u6253\u5370\u9519\u8bef\u7684\u53d8\u91cf\u503c, \u8ddflog\u7684\u503c\u4e0d\u4e00\u6837, \u63a8\u8350\u5c3d\u91cf\u6253log, log\u91cc\u9762\u7684\u503c\u4e00\u5b9a\u662f\u6b63\u786e\u7684, gdb\u91cc\u9762\u4e0d\u4e00\u5b9a 4) \u590d\u6742\u7c7b\u578b\u53d8\u91cf<\/p>\n
gdb\u652f\u6301pretty printer<\/code>, \u53ef\u4ee5\u8ba9\u590d\u6742\u7c7b\u578b\u770b\u8d77\u6765\u66f4\u8212\u670d\u4e00\u4e9b<\/p>\n
   (gdb) set print pretty on\r\n   (gdb) p *this\r\n   $2 = {\r\n    <gsdk::Singleton<gsdk::message::MainLoop>> = {\r\n        <gsdk::Noncopyable> = {<No data fields>}, \r\n        members of gsdk::Singleton<gsdk::message::MainLoop>:\r\n        static once_ = {\r\n            _M_once = 2\r\n        }, \r\n        static ptr_ = 0x612000000ac0\r\n    }, \r\n    members of gsdk::message::MainLoop: \r\n    run_ = true, \r\n<\/code><\/pre>\n
gdb\u53ef\u4ee5\u901a\u8fc7python\u63d2\u4ef6\u6269\u5c55\u6765\u652f\u6301\u4e2a\u590d\u6742\u7c7b\u578b\u7684\u6253\u5370, \u4f8b\u5982STL\u7b49, Ubuntu\u7b49\u53d1\u884c\u7248\u81ea\u5e26\u4e86STL\u7684pretty printer.<\/p>\n
   (gdb) p this->queue_.queue_ \r\n   $4 = std::vector of length 0, capacity 1\r\n<\/code><\/pre>\n
5)<\/p>\n
\n
\u53c2\u8003\u8d44\u6599<\/h3>\n<\/div>\n
1)\u00a0GDB User Mannual<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u7f16\u8bd1\u9009\u9879 \u8981\u8c03\u8bd5C\/C++\u7684\u7a0b\u5e8f\uff0c\u5728\u7f16\u8bd1<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[118],"class_list":["post-4278","post","type-post","status-publish","format-standard","hentry","tag-02-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4278","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=4278"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4278\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=4278"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=4278"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=4278"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}