Commit: gas: Improve DWARF2 fixed increments

nick clifton nickc@redhat.com
Wed Mar 20 16:52:00 GMT 2013


Hi Alan,

>>    when the target uses linker relaxation).  The enhancement simply omits
>>    the line increment if the line delta is zero and omits the address
>>    increment if the address delta is zero.

> Does the comment about GDB using duplicate line info no longer apply?
>
>    /* Don't emit sequences of line symbols for the same line when the
>       symbols apply to assembler code.  It is necessary to emit
>       duplicate line symbols when a compiler asks for them, because GDB
>       uses them to determine the end of the prologue.  */

Yes-ish.  For the targets that use fixed line increments the answer is 
"yes".  For targets that do not use fixed line increments (which is the 
majority) the answer is "I do not know".  I have not checked how GDB 
analyses prologues for all of these targets, so I did not propagate my 
optimization to the non-fixed-line code.

Cheers
   Nick




More information about the Binutils mailing list