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Maciej W. Rozycki 9875b36538 GAS: Fix bogus "attempt to move .org backwards" relaxation errors
Fix a commit 6afe8e98a6 ("internal error for backwards .org"),
<https://www.sourceware.org/ml/binutils/2008-06/msg00212.html>,
GAS regression that caused legitimate code to fail assembly with an
"attempt to move .org backwards" error.

For example with the `mips-linux' target we get:

$ cat org.s
	.set	mips16
	la	$2, foo
	.org	0x1000
	.align	2
foo:
	.half	0
$ as -o org.o org.s
org.s: Assembler messages:
org.s:3: Error: attempt to move .org backwards
$

where the location pointer is obviously not moved backwards with `.org'.

The cause is positive `stretch' in relaxation due to a PC-relative ADDIU
instruction (produced from the LA macro used) getting expanded from 2 to
4 bytes as `foo' is noticed to be out of range for the short encoding.
This in turn triggers logic in `relax_segment' which concludes in the
processing of an `rs_org' frag produced that the location pointer is
moved backwards while in fact only the amount to space forward to the
location requested has shrunk, resulting in a negative growth of the
frag.

Correct the bad logic then and instead verify that the fixed part of an
`rs_org' frag has not overrun the location requested, as per the comment
already included with the error message:

/* Growth may be negative, but variable part of frag
   cannot have fewer than 0 chars.  That is, we can't
   .org backwards.  */

which accurately describes the regression scenario.  Move the comment
ahead the conditional noted, for clarity.

Add generic and MIPS test cases for the `.org' pseudo-op, including the
test case discussed though not integrated with the offending commit in
particular, adjusted to work across all targets.

	gas/
	* write.c (relax_segment) <rs_org>: Only bail out if the fixed
	part of the frag has overrun the location requested.

	* testsuite/gas/all/org-1.d: New test.
	* testsuite/gas/all/org-2.d: New test.
	* testsuite/gas/all/org-3.d: New test.
	* testsuite/gas/all/org-4.d: New test.
	* testsuite/gas/all/org-5.d: New test.
	* testsuite/gas/all/org-6.d: New test.
	* testsuite/gas/all/org-1.l: New stderr output.
	* testsuite/gas/all/org-2.l: New stderr output.
	* testsuite/gas/all/org-3.l: New stderr output.
	* testsuite/gas/all/org-1.s: New test source.
	* testsuite/gas/all/org-2.s: New test source.
	* testsuite/gas/all/org-3.s: New test source.
	* testsuite/gas/all/org-4.s: New test source.
	* testsuite/gas/all/org-5.s: New test source.
	* testsuite/gas/all/org-6.s: New test source.
	* testsuite/gas/all/gas.exp: Run the new tests.

	* testsuite/gas/mips/org-1.d: New test.
	* testsuite/gas/mips/org-2.d: New test.
	* testsuite/gas/mips/org-3.d: New test.
	* testsuite/gas/mips/org-4.d: New test.
	* testsuite/gas/mips/org-5.d: New test.
	* testsuite/gas/mips/org-6.d: New test.
	* testsuite/gas/mips/org-7.d: New test.
	* testsuite/gas/mips/org-8.d: New test.
	* testsuite/gas/mips/org-9.d: New test.
	* testsuite/gas/mips/org-10.d: New test.
	* testsuite/gas/mips/org-11.d: New test.
	* testsuite/gas/mips/org-12.d: New test.
	* testsuite/gas/mips/org-1.l: New stderr output.
	* testsuite/gas/mips/org-4.l: New stderr output.
	* testsuite/gas/mips/org-5.l: New stderr output.
	* testsuite/gas/mips/org-6.l: New stderr output.
	* testsuite/gas/mips/org-10.l: New stderr output.
	* testsuite/gas/mips/org-1.s: New test source.
	* testsuite/gas/mips/org-2.s: New test source.
	* testsuite/gas/mips/org-3.s: New test source.
	* testsuite/gas/mips/org-4.s: New test source.
	* testsuite/gas/mips/org-5.s: New test source.
	* testsuite/gas/mips/org-6.s: New test source.
	* testsuite/gas/mips/org-7.s: New test source.
	* testsuite/gas/mips/org-8.s: New test source.
	* testsuite/gas/mips/org-9.s: New test source.
	* testsuite/gas/mips/org-10.s: New test source.
	* testsuite/gas/mips/org-11.s: New test source.
	* testsuite/gas/mips/org-12.s: New test source.
	* testsuite/gas/mips/mips.exp: Run the new tests.
2017-03-02 01:44:07 +00:00
bfd PowerPC VLE typo fix 2017-03-02 10:40:06 +10:30
binutils Add support for displaying and merging GNU_BUILD_NOTEs. 2017-03-01 11:09:46 +00:00
config
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elfcpp
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gas GAS: Fix bogus "attempt to move .org backwards" relaxation errors 2017-03-02 01:44:07 +00:00
gdb GDB: Add support for the new set/show disassembler-options commands. 2017-02-28 12:32:07 -06:00
gold PowerPC ld segfault on script discarding dynamic sections 2017-02-22 08:44:41 +10:30
gprof
include Add support for displaying and merging GNU_BUILD_NOTEs. 2017-03-01 11:09:46 +00:00
intl
ld Avoid gcc-7 warning killing ld testcases 2017-03-02 10:40:06 +10:30
libdecnumber
libiberty Sync libiberty sources with GCC mainline. 2017-03-01 15:09:29 +00:00
opcodes GDB: Add support for the new set/show disassembler-options commands. 2017-02-28 12:32:07 -06:00
readline
sim Add missing smov support, and clean up existing umov support. 2017-02-25 20:06:36 -08:00
texinfo
zlib Sync ZLIB with FSF GCC sources, bringing in version 1.2.11. 2017-02-20 12:52:22 +00:00
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