Bug#558999: FTBFS [hppa] - recompile with -ffunction-sections

[James Bottomley]

> I am not very good at GCC optimizations. Can you please explain why
> this problem is not seen on other architectures? Also can you please
> advise if I should add this compiler option for all arch or just hppa.

It's not really a gcc problem, it's an ELF one.  The ELF spec for HPPA
says that we need to leave symbol resolution as a relative jump.  On
parisc 32 bits, this is a 17bit relative jump.  We can do longer by
indirecting through a stub section.  However, this problem usually
occurs because the actual text section of the .o file is bigger than
131k (about 17 bits) and so the linker can't insert a reachable stub
into the binary.

-ffunction-sections splits the text section up into one section per
function, so now the linker can insert the stubs in between the
functions and thus the problem is solved (until a single function gets
longer than 131k).

Most other architectures have bigger relative jumps, so they likely
won't need -ffunction-sections (unless the file you're compiling gets
much bigger).

James