Nick Clifton
Fri, 22 Feb 2008 03:29:52 -0800
Hi Sergei,
LD version 2.18.x produces bogus "section .xxx overlaps section .bss", while LD version 2.16.1 works just fine.
Well the 2.18 linker is behaving as documented. Specifically in the bit on the "Output Section LMA" in the manual:
If neither AT nor AT> is specified for an allocatable section, the linker will set the LMA such that the difference between VMA and LMA for the section is the same as the preceding output section in the same region.Since the .bss section does not have an AT or an AT> directive its LMA is set to 0x110, so that difference between its VMA (0x4110), as set by the "> RAM" directive, and its LMA is 0x4000, ie the same as the difference between the VMA and the LMA of the .data section. (Try running the linker with the --no-check-sections option and then looking at the section headers to see this).
This is a change in the linker's behaviour that was made for the 2.18 release. There is even a mention of it in the NEWS file.
It does suggest a workaround for the problem: Change the "> RAM" in the description of the .bss section to "AT> RAM". ie:
.bss : {
. += 0x120;
} AT> RAM
According to the manual this will set both the LMA and the VMA for the
section, and you will end up with the same behaviour as the 2.16 linker.
(This change is backwards compatible, i.e. it will work with the 2.16
linker as well). Unfortunately there is a bug in the current linker
sources such that the "AT> [region-name]" syntax is ignored unless there
is also an "> [region-name-2]" specified for the section, and the two
regions are different. I can see no good reason for this, and the
behaviour certainly isn't documented, so I am planning to check in the
uploaded patch to remove this restriction unless my regression testing
shows up a problem.
Cheers Nick _______________________________________________ bug-binutils mailing list bug-binutils@gnu.org http://lists.gnu.org/mailman/listinfo/bug-binutils