Optimizations of functions (-O1 & -O2)

[Rob Emanuele]

I compiling C++ code on an SGI using GCC and I'm trying to
make a debug build with no optimizations.  The code base is
quite large so I'm trying to use as few source files as
possible.

If I specify the -O2 optimize option things compile OK but
are hard to debug.  If I do use not optimizations or
use -O1, I have linking problems that result in messages
like these:

ld32: ERROR 33: Unresolved text symbol
"hsQuat::Read(hsStream *)" -- 1st referenced by
hsKeys.dbg.o.
	Use linker option -v to see when and which objects,
archives and dsos are loaded.
ld32: ERROR 33: Unresolved text symbol
"hsQuat::Write(hsStream *)" -- 1st referenced by
hsKeys.dbg.o.
	Use linker option -v to see when and which objects,
archives and dsos are loaded.
ld32: ERROR 33: Unresolved text symbol "decomp_affine(float
const (*)[3], gemAffineParts *)" -- 1st referenced by
hsKeys.dbg.o.
	Use linker option -v to see when and which objects,
archives and dsos are loaded.
ld32: ERROR 33: Unresolved text symbol
"hsAffineParts::Read(hsStream *)" -- 1st referenced by
hsKeys.dbg.o.
	Use linker option -v to see when and which objects,
archives and dsos are loaded.
ld32: ERROR 33: Unresolved text symbol
"hsAffineParts::Write(hsStream *)" -- 1st referenced by
hsKeys.dbg.o.
	Use linker option -v to see when and which objects,
archives and dsos are loaded.

Does anyone know what single optimization I can turn on to
optimize these out?  I'm pretty sure that none of these
functions are actually used.  Does anyone know what
specifically the optimizations are that -O1 & -O2 turn on or
where that info lives?

Thanks,

Rob