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Re: Repost: Inaccurate function parameter location in debug info with gcc 3.x and 4.0
Hi -
> [...] Below is the relevant debug info generated by "readelf -wi
> vmlinux". The kernel is 2.6.14.7 and the compiler is gcc 3.4.4. The
> function of interest is sys_read. [...]
(Thanks for the eu-readelf information, though it is not by itself
enough to diagnose the problem. One might need more bits like a
disassembly of the probed function, address-related excerpts from
"stap -vvvv" output.)
> In my system, this is very easily reproducible. You just need to
> compile the kernel using gcc 3.x with -O2 and -Os.
Red Hat originated kernels are built with -Os, but, importantly, use
newer compilers that include fixes related to debugging information.
> Please help me verify if this is just my build system's problem or
> it is a common problem affecting all users. [...]
It is not a common problem. We have a standard example in the test
suite (iotask*.stp) that, although we don't run it automatically for
some reason (no .exp file), it does work when run by hand.
- FChE