rpm/elfutils/NOTES

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- old GNU ld's behavior wrt DSOs seems to be severely broken.
y.o reference foo()
y1.o defines foo(), references bar()
y2.o defines bar()
libbar.so defines bar()
Running
gcc -o y y.o -lbar y1.o y2.o
uses the bar() definition from libbar.so and does not mention the definition
in y2.o at all (no duplicate symbol message). Correct is to use the
definition in y2.o.
y.o reference foo()
y1.o defines foo(), references bar()
y2.o in liby2.a defines bar()
libbar.so defines bar()
Running
gcc -o y y.o -lbar y1.o -ly3
has to use the definition in -lbar and not pull the definition from liby3.a.
- the old linker follows DT_NEEDED entries and adds the objects referenced
this way which define a symbol which is needed as a DT_NEEDED to the
generated binary. This is wrong since the DT_NEEDED changes the search
path in the object (which is breadth first).
- the old linker supported extern "C++", extern "java" in version scripts.
I believe this implementation is severly broken and needs a redesign
(how do wildcards work with these languages*?). Therefore it is left
out for now.
- what should happen if two sections in different files with the same
name have different types and/or the flags are different
- section names in input files are mostly irrelevant. Exceptions:
.comment/SHT_PROGBITS in strip, ld
.debug \
.line |
.debug_srcinfo |
.debug_sfnames |
.debug_aranges |
.debug_pubnames |
.debug_info |
.debug_abbrev |
.debug_line |
.debug_abbrev > DWARF sections in ld
.debug_line |
.debug_frame |
.debug_str |
.debug_loc |
.debug_macinfo |
.debug_weaknames |
.debug_funcnames |
.debug_typenames |
.debug_varnames /
Sections created in output files follow the naming of special section
from the gABI.
In no place is a section solely indentified by its name. Internal
references always use the section index.