Mickael Guene 72d98d16ed [ARM] Add support for thumb1 pcrop relocations.
To support thumb1 execute-only code we need to support four new
relocations (R_ARM_THM_ALU_ABS_G0_NC, R_ARM_THM_ALU_ABS_G1_NC,
R_ARM_THM_ALU_ABS_G2_NC and  R_ARM_THM_ALU_ABS_G3_NC).
These relocations allow the static linker to finalize construction
of symbol address.
Typical sequence of code to get address of the symbol foo is then
the following :
	movs	r3, #:upper8_15:#foo
	lsls	r3, #8
	adds	r3, #:upper0_7:#foo
	lsls	r3, #8
	adds	r3, #:lower8_15:#foo
	lsls	r3, #8
	adds	r3, #:lower0_7:#foo
This will give following sequence of text and relocations after
assembly :
   4:	2300      	movs	r3, #0
			4: R_ARM_THM_ALU_ABS_G3_NC	foo
   6:	021b      	lsls	r3, r3, #8
   8:	3300      	adds	r3, #0
			8: R_ARM_THM_ALU_ABS_G2_NC	foo
   a:	021b      	lsls	r3, r3, #8
   c:	3300      	adds	r3, #0
			c: R_ARM_THM_ALU_ABS_G1_NC	foo
   e:	021b      	lsls	r3, r3, #8
  10:	3300      	adds	r3, #0
			10: R_ARM_THM_ALU_ABS_G0_NC	foo
2015-12-16 10:19:51 +01:00
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		README for LD

This is the GNU linker.  It is distributed with other "binary
utilities" which should be in ../binutils.  See ../binutils/README for
more general notes, including where to send bug reports.

There are many features of the linker:

* The linker uses a Binary File Descriptor library (../bfd)
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* The linker can be configured for cross-linking.

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Installation
============

See ../binutils/README.

If you want to make a cross-linker, you may want to specify
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You can do this by setting the LIB_PATH variable in ./Makefile
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To build just the linker, make the target all-ld from the top level
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Porting to a new target
=======================

See the ldint.texinfo manual.

Reporting bugs etc
===========================

See ../binutils/README.

Known problems
==============

The Solaris linker normally exports all dynamic symbols from an
executable.  The GNU linker does not do this by default.  This is
because the GNU linker tries to present the same interface for all
similar targets (in this case, all native ELF targets).  This does not
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HP/UX 9.01 has a shell bug that causes the linker scripts to be
generated incorrectly.  The symptom of this appears to be "fatal error
- scanner input buffer overflow" error messages.  There are various
workarounds to this:
  * Build and install bash, and build with "make SHELL=bash".
  * Update to a version of HP/UX with a working shell (e.g., 9.05).
  * Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
    genscripts.sh with "sh ${srcdir}..." (no parens) and make sure the
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