Re:[Patch]linuxppc gnuplot segfaults in save

Re:[Patch]linuxppc gnuplot segfaults in save

[Dean Luick]

> Here is a minimal example, adapted from the gnuplot sources. If used
as
> "a.out foo.gnu", it segfaults for me. Compiler is egcs-2.91.66
19990314
> (egcs-1.1.2 release) (PowerPC GNU/Linux), glibc-2.1.1-3a.
> gbd backtrace gives

Using egcs 1.0.2 prelease, it looks like egcs is messing up how it
pushes
arguements on the stack.  In partiuclar, egcs should be filling all of
the integer
argument registers, r3-r10.  Instead, it places what should to in r8 in
r10, and placing
what should be in r9 and r10 on the stack.  This leave r8 and r9
completely random, plus
pushes the final two integer arguments (which should be on the stack) 8
bytes off from
their correct position.

Assuming that fprintf correctly interprets the format string, it is no
wonder that
it crashes.

Dean



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Re: [Patch]linuxppc gnuplot segfaults in save

[David Edelsohn]

	You can try invoking EGCS with the additional commandline argument
-mdebug-arg for it to print out additional information about how it is
advancing through the arguments of functions and figure out where in
rs6000.c:function_arg() it is not matching what fprintf expects.  FP gets
very complicated.

David

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