[Bug target/64569] New: [MIPS] Unable to build soft-float in conjunction with binutils 2.25

[Bug target/64569] New: [MIPS] Unable to build soft-float in conjunction with binutils 2.25

[matthew.fortune at imgtec dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64569

            Bug ID: 64569
           Summary: [MIPS] Unable to build soft-float in conjunction with
                    binutils 2.25
           Product: gcc
           Version: 4.9.3
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: matthew.fortune at imgtec dot com

binutils 2.25 for MIPS includes more aggressive checks on ABI usage and in
particular warns when given code that claims to be soft-float via
.gnu_attribute 4,3 but is assembled without -msoft-float. binutils 2.25 will
also infer an ABI from the floating-point related command line options.

No GCC compiler drivers prior to GCC 5.0 pass the -msoft-float option through
to the assembler which means that the assembler is given an inconsistent view
of the intended ABI.

For compiled code the issue will show itself as a warning from the assembler:
Warning: .gnu_attribute 4,3 requires `softfloat'

For hand-crafted assembler modules assembled via the compiler driver then the
ABI inferred by the assembler will be hard-float instead of soft-float owing to
the missing -msoft-float option.

A combination of these two problems will then lead to a link failure stating
that incompatible ABIs are in use. A number of other relocation errors can also
occur as a side effect.

(This bug was also filed as a binutils issue but is actually a compiler driver
issue: https://sourceware.org/bugzilla/show_bug.cgi?id=17219)

[Bug target/64569] [4.8/4.9 only] [MIPS] Unable to build soft-float in conjunction with binutils 2.25

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64569

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |5.0
   Target Milestone|---                         |4.9.4
            Summary|[MIPS] Unable to build      |[4.8/4.9 only] [MIPS]
                   |soft-float in conjunction   |Unable to build soft-float
                   |with binutils 2.25          |in conjunction with
                   |                            |binutils 2.25
           Severity|major                       |normal

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed in GCC 5 already.

[Bug target/64569] [4.8/4.9 only] [MIPS] Unable to build soft-float in conjunction with binutils 2.25

[mpf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64569

--- Comment #2 from mpf at gcc dot gnu.org ---
Author: mpf
Date: Thu Feb 26 10:56:09 2015
New Revision: 221001

URL: https://gcc.gnu.org/viewcvs?rev=221001&root=gcc&view=rev
Log:
Add missing bug number to r221000

    PR target/64569
    * See r221000

Modified:
    branches/gcc-4_9-branch/gcc/ChangeLog