如何使用 lldb（或 gdb）调试 Clang 插件

Question

我想调试 Clang 插件。
但是，我找不到有关调试 Clang 插件的信息。
如果你知道如何调试 Clang 插件，你能告诉我这些信息吗？ 谢谢。

Answer 1

只是一个小轮廓，因为我自己正在尝试这个 atm。我正在使用 lldb。

我目前能够在插件中的任何给定功能处停止，但缺少源代码。它只显示程序集。

当您使用-Xclang -plugin (...) 调用clang 时，它将分叉到一个子进程中。调用插件时，还要传递-v 选项以查看子进程命令行。然后在调试器中使用这个命令行。

原始命令行：

$> clang++ -Xclang -load -Xclang ${PLUGIN} -Xclang -plugin -Xclang cgd -std=c++11 -w -fsyntax-only -v

应该输出：

clang version 3.1 (tags/RELEASE_31/final 163510)
Target: x86_64-unknown-linux-gnu
Thread model: posix
 "/srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/clang-3.1" -cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -disable-free -main-file-name call_in_if.cpp -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -momit-leaf-frame-pointer -v -resource-dir /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1
-fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6
-internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/x86_64-linux-gnu
-internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/backward
-internal-isystem /usr/local/include -internal-isystem /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1/include
-internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Werror -w -std=c++11 -fdeprecated-macro
-fdebug-compilation-dir /srv/scratch/sigubufo/danceos_wd/clang/qtcreator-build -ferror-limit
19 -fmessage-length 205 -mstackrealign -fgnu-runtime
-fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fcxx-exceptions -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -load lib/CallGraphDumper.so -plugin cgd -x c++ ../test_cases/call_in_if.cpp
clang -cc1 version 3.1 based upon LLVM 3.1svn default target x86_64-unknown-linux-gnu
ignoring nonexistent directory "/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6
 /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/x86_64-linux-gnu
 /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/backward
 /usr/local/include
 /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1/include
 /usr/include/x86_64-linux-gnu
 /usr/include
End of search list.

这是你需要的部分：

"/srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/clang-3.1" -cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -disable-free -main-file-name call_in_if.cpp -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -momit-leaf-frame-pointer -v -resource-dir /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1 -fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/x86_64-linux-gnu -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/backward -internal-isystem /usr/local/include -internal-isystem /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Werror -w -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /srv/scratch/sigubufo/danceos_wd/clang/qtcreator-build -ferror-limit 19 -fmessage-length 205 -mstackrealign -fgnu-runtime -fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fcxx-exceptions -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -load lib/CallGraphDumper.so -plugin cgd -x c++ ../test_cases/call_in_if.cpp

现在你调用 lldb：

lldb "/srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/clang-3.1"

然后在 lldb 提示符下进行操作

(lldb) break set --name YourPlugin::FunctionToBreakAt

(lldb) process launch -- -cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -disable-free -main-file-name call_in_if.cpp -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -momit-leaf-frame-pointer -v -resource-dir /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1 -fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/x86_64-linux-gnu -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../../include/c++/4.6/backward -internal-isystem /usr/local/include -internal-isystem /srv/scratch/sigubufo/clang/stable/3.1_src/build/bin/../lib/clang/3.1/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Werror -w -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /srv/scratch/sigubufo/danceos_wd/clang/qtcreator-build -ferror-limit 19 -fmessage-length 205 -mstackrealign -fgnu-runtime -fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fcxx-exceptions -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -load lib/CallGraphDumper.so -plugin cgd -x c++ ../test_cases/call_in_if.cpp

这应该可行。