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4ec192e6ab
It's generally a bad idea to use assertions to validate our idea of
what an input file looks like. We need to be as liberal as possible
in what we accept with respect to standards and conservative with what
we produce.
Currently, if gcc is used to produce an assembler file which contains
only data, but the FPU is set to fpv4-sp-d16 and mfloat-abi=hard, then
the following attributes will be set in the output:
.cpu arm7tdmi
.eabi_attribute 27, 1 @ Tag_ABI_HardFP_use
.eabi_attribute 28, 1 @ Tag_ABI_VFP_args
.eabi_attribute 20, 1 @ Tag_ABI_FP_denormal
.eabi_attribute 21, 1 @ Tag_ABI_FP_exceptions
.eabi_attribute 23, 3 @ Tag_ABI_FP_number_model
.eabi_attribute 24, 1 @ Tag_ABI_align8_needed
.eabi_attribute 25, 1 @ Tag_ABI_align8_preserved
.eabi_attribute 26, 2 @ Tag_ABI_enum_size
.eabi_attribute 30, 6 @ Tag_ABI_optimization_goals
.eabi_attribute 34, 0 @ Tag_CPU_unaligned_access
.eabi_attribute 18, 4 @ Tag_ABI_PCS_wchar_t
There is then no .fpu directive to cause Tag_FP_arch to be set,
because there are no functions containing code in the object file. If
this object file is assembled by hand, but without -mfpu on the
invocation of the assembler, then the build attributes produced will
trigger an assertion during linking.
Thinking about the build attributes, the combination of a
single-precision only implementation of no floating-point architecture
is still no floating-point architecture. Hence the assertion on the
input BFD in the linker makes no real sense.
We should, however, be more conservative in what we generate, so I've
left the assertion on the output bfd in place; I don't think we can
trigger it with this change since we never merge the problematic tags
from a perversely generated input file.
* elf32-arm.c (elf32_arm_merge_eabi_attributes): Remove assertion
that the input bfd has Tag_FP_ARCH non-zero if Tag_ABI_HardFP_use
is non-zero. Add clarifying comments.
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. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.