无法设置gdb断点

Question

I work on program with multiple C++ files. I have run the executable through gdb for debugging segmentation fault. Later, gdb backtrace provided the list of functions before segmentation fault. Later, I tried to set a break point in a file on a particular line-number. (The path specified is absolute path)

(gdb) break /aia/r015/home/sathish/zfs_amr/src/zfslbminterfaced2q9.cpp:100

However, gdb gives the following message:

No source file named /aia/r015/home/sathish/zfs_amr/src/zfslbminterfaced2q9.cpp.

However, this particular does exist in the location. What really the message means?

Answer 1

What really the message means?

The message means that GDB does not know about any source file named /aia/r015/home/sathish/zfs_amr/src/zfslbminterfaced2q9.cpp .

There are multiple reasons this could be the case:

• The debug info for this file is missing, either because that file is compiled without -g , or because the debug info was (possibly inadvertantly) stripped later on,
• There are some symbolic links in the above path, and GDB knows that file by fully-resolved pathname instead,
• The file is actually not linked into the executable at all,
• The file part of a shared library, and symbols for that shared library haven't been loaded yet,
• Etc.

As Pat suggested, setting breakpoint on zfslbminterfaced2q9.cpp:100 is more likely to work.

If that doesn't work, info sources will tell you which files GDB does know about.

Update:

info sources gives blank

This means that the application doesn't have any debug info at all .

Usually this happens for one of two reasons:

• You neglected to specify -g on the link line (some platforms require -g both at compile and link time),
• You have a "stray" -s somewhere on your link line (which strips the final executable).