Binutils with MCST patches
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Maciej W. Rozycki b416ba9b50 MIPS/GAS: Don't convert PC-relative REL relocs against absolute symbols
Don't convert PC-relative REL relocations against absolute symbols to
section-relative references and retain the original symbol reference
instead.  Offsets into the absolute section may overflow the limited
range of their in-place addend field, causing an assembly error, e.g.:

$ cat test.s
	.text
	.globl	foo
	.ent	foo
foo:
	b	bar
	.end	foo

	.set	bar, 0x12345678
$ as -EB -32 -o test.o test.s
test.s: Assembler messages:
test.s:3: Error: relocation overflow
$

With the original reference retained the source can now be assembled and
linked successfully:

$ as -EB -32 -o test.o test.s
$ objdump -dr test.o

test.o:     file format elf32-tradbigmips

Disassembly of section .text:

00000000 <foo>:
   0:	1000ffff 	b	0 <foo>
			0: R_MIPS_PC16	bar
   4:	00000000 	nop
	...
$ ld -melf32btsmip -Ttext 0x12340000 -e foo -o test test.o
$ objdump -dr test

test:     file format elf32-tradbigmips

Disassembly of section .text:

12340000 <foo>:
12340000:	1000159d 	b	12345678 <bar>
12340004:	00000000 	nop
	...
$

For simplicity always retain the original symbol reference, even if it
would indeed fit.

Making TC_FORCE_RELOCATION_ABS separate from TC_FORCE_RELOCATION causes
R_MICROMIPS_PC7_S1, R_MICROMIPS_PC10_S1 and R_MICROMIPS_PC16_S1 branch
relocations against absolute symbols to be converted on RELA targets to
section-relative references.  This is an intended effect of this change.
Absolute symbols carry no ISA annotation in their `st_other' field and
their value is not going to change with linker relaxation, so it is safe
to discard the original reference and keep the calculated final symbol
value only in the relocation's addend.

Similarly R6 R_MIPS_PCHI16 and R_MIPS_PCLO16 relocations referring
absolute symbols can be safely converted even on REL targets, as there
the in-place addend of these relocations covers the entire 32-bit
address space so it can hold the calculated final symbol value, and
likewise the value referred won't be affected by any linker relaxation.

Add a set of suitable test cases and enable REL linker tests which now
work and were previously used as dump patterns for RELA tests only.

	gas/
	* config/tc-mips.h (TC_FORCE_RELOCATION_ABS): New macro.
	(mips_force_relocation_abs): New prototype.
	* config/tc-mips.c (mips_force_relocation_abs): New function.
	* testsuite/gas/mips/branch-absolute.d: Adjust dump patterns.
	* testsuite/gas/mips/mips16-branch-absolute.d: Likewise.
	* testsuite/gas/mips/micromips-branch-absolute-n32.d: Likewise.
	* testsuite/gas/mips/micromips-branch-absolute-n64.d: Likewise.
	* testsuite/gas/mips/micromips-branch-absolute-addend-n32.d:
	Likewise.
	* testsuite/gas/mips/micromips-branch-absolute-addend-n64.d:
	Likewise.
	* testsuite/gas/mips/branch-absolute-addend.d: New test.
	* testsuite/gas/mips/mips16-branch-absolute-addend.d: New test.
	* testsuite/gas/mips/micromips-branch-absolute-addend.d: New
	test.
	* testsuite/gas/mips/mips.exp: Run the new tests.

	ld/
	* testsuite/ld-mips-elf/mips-elf.exp: Run
	`branch-absolute-addend', `mips16-branch-absolute',
	`mips16-branch-absolute-addend' and
	`micromips-branch-absolute-addend'.
2016-07-14 20:11:03 +01:00
bfd BFD: Let targets handle relocations against absolute symbols 2016-07-14 20:06:37 +01:00
binutils objcopy/strip: Add option --remove-relocations=SECTIONPATTERN 2016-07-14 11:34:10 +01:00
config
cpu
elfcpp Add support for MIPS .rld_map section. 2016-06-20 12:16:26 -07:00
etc Fix compile time warning messages building with gcc v6.1.1 2016-06-13 10:49:26 +01:00
gas MIPS/GAS: Don't convert PC-relative REL relocs against absolute symbols 2016-07-14 20:11:03 +01:00
gdb Add missing newline to py-breakpoint.c 2016-07-14 11:51:12 -06:00
gold Fix gold testsuite failure with GCC 6. 2016-06-29 23:24:35 -07:00
gprof
include [ARC] Fix/improve small data support. 2016-07-14 10:08:57 +02:00
intl
ld MIPS/GAS: Don't convert PC-relative REL relocs against absolute symbols 2016-07-14 20:11:03 +01:00
libdecnumber
libiberty Don't needlessly clear xmemdup allocated memory. 2016-05-31 20:34:47 +09:30
opcodes MIPS/opcodes: Address issues with NAL disassembly 2016-07-13 17:42:43 +01:00
readline
sim Small improvements to the ARM simulator to cope with illegal binaries. 2016-07-14 10:38:07 +01:00
texinfo
zlib
.cvsignore
.gitattributes
.gitignore
COPYING
COPYING.LIB
COPYING.LIBGLOSS
COPYING.NEWLIB
COPYING3
COPYING3.LIB
ChangeLog [TILEPro] Don't build gdb 2016-06-28 14:16:15 -04:00
MAINTAINERS
Makefile.def
Makefile.in Add dependencies to configure rule 2016-05-28 22:36:04 +09:30
Makefile.tpl Add dependencies to configure rule 2016-05-28 22:36:04 +09:30
README
README-maintainer-mode
compile
config-ml.in
config.guess Fix typo introduced during the most recent synchronization update. 2016-05-27 14:34:06 +01:00
config.rpath
config.sub
configure [TILEPro] Don't build gdb 2016-06-28 14:16:15 -04:00
configure.ac [TILEPro] Don't build gdb 2016-06-28 14:16:15 -04:00
depcomp
djunpack.bat
install-sh
libtool.m4
ltgcc.m4
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README

		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
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see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

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tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

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then do:
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