[Bug debug/10000] gcc -g generates location expressions which are not valid in prologue

[dberlin@gcc.gnu.org]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10000


dberlin@gcc.gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


------- Additional Comments From dberlin@gcc.gnu.org  2003-06-16 03:36 -------
GCC provides the information for *source level* debugging, not *assembly
instruction level* debugging.
Thus, we don't guarantee, even without optimization, that stepping asm
instruction by asm instruction will print out the correct results at each point
for a variable.
If you really want instruction level debugging info, the cfg-branch can generate
it with the dwarf2 location list stuff i added there + the var-tracking pass
added by others.
This will never be the default (though we might introduce a -g4, eventually, but
i  certainly don't want to support it), because the cost in terms of debug info
size is humongous, and the benefit is almost non-existent for the majority of
programmers.
It's also pretty expensive (cpu time wise) to generate it at that level of
granularity anyway.
--Dan