debug

Updated in 2024-08.

Note: The article will likely get frequent updates in the next few days.

This article describes some approaches to distribute debug information. Commands below will use two simple C files for demonstration.

cat > a.c <<eof
void foo(int);
int main() { foo(42); }
eof
cat > b.c <<eof
#include <stdio.h>
void foo(int x) { printf("%d\n", x); }
eof

Deterministic builds with clang and lld describes several degrees of build determinism. Here is the description of local determinism:

Like incremental basic determinism, but builds are also independent of the name of the build directory. Builds of the same source code on the same machine produce exactly the same output every time, independent of the location of the source checkout directory or the build directory.

我喜欢基于代码片段的学习，之前学习过一些binutils和其他处理ELF的工具的奇技淫巧，了解到很多概念，比如weak symbol、common section、RPATH、把资源文件嵌入ELF等，昨天创建了一个项目https://github.com/MaskRay/ElfHacks整理了很多自包含的例子。

之前写过一篇《Debug Hacks》和调试技巧。

CFLAGS使用-g3

对于重度使用macro的程序很有用，可以在gdb里使用info macro NAME、macro expand EXPR等命令了，print参数里的macro也可以展开。