[Bug target/42100] New: soft float flags missings from libgcc.a (and others) if no --with-float given at configure time

[Bug target/42100] New: soft float flags missings from libgcc.a (and others) if no --with-float given at configure time

[schodet at efrei dot fr]

This is similar to #14895.

On arm-elf target, the compiler defaults to soft-float even when no option is
passed.  Binutils defaults to hard-float (it sets the SOFTFLOAT only if the
soft-float option is given).  When libgcc is built for soft-float, gas receives
no option from gcc and therefore does not set the SOFTFLOAT flag.

This is shown using arm-elf-objdump -p on the libgcc.a file ([software FP]
missing).

A workaround is to provide an explicit --with-float=soft at configure time. In
this case, this is added to configure_default_options, and OPTION_DEFAULT_SPECS
saves us.

Configured with: /home/nico/arm/gcc-arm-elf-4.3.2/src/configure
--prefix=/usr/lib --infodir=/usr/share/info --mandir=/usr/share/man
--datadir=/usr/share --bindir=/usr/bin --libexecdir=/usr/lib --libdir=/usr/lib
--build=i486-linux-gnu --host=i486-linux-gnu --target=arm-elf
--enable-languages=c --enable-shared --with-system-zlib --enable-nls
--without-included-gettext --disable-checking --disable-libssp
--enable-interwork --enable-multilib

I use a customised t-arm-elf to build multilib with hard and soft float.

Thanks.


-- 
           Summary: soft float flags missings from libgcc.a (and others) if
                    no --with-float given at configure time
           Product: gcc
           Version: 4.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: schodet at efrei dot fr
 GCC build triplet: all
  GCC host triplet: all
GCC target triplet: arm-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42100

[Bug target/42100] soft float flags missings from libgcc.a (and others) if no --with-float given at configure time

[schodet at efrei dot fr]

------- Comment #1 from schodet at efrei dot fr  2009-11-18 23:43 -------
Created an attachment (id=19037)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=19037&action=view)
Modified t-arm-elf

Lines have been commented out to enable a more flexible multilib.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42100

[Bug target/42100] soft float flags missings from libgcc.a (and others) if no --with-float given at configure time

[rearnsha at gcc dot gnu dot org]

------- Comment #2 from rearnsha at gcc dot gnu dot org  2009-11-21 10:56 -------
This is a known problem, but I'm not going to fix it.  The difficulty is that
it will break object compatibility for a large number of users upgrading from
older versions of the compiler (the attributes will conflict) forcing them to
recompile everything (and in some cases that's not possible).

The attribute system used in the arm-elf configuration is very primitive and
not extensible, so it was entirely reworked as part of the ARM ABI
standardization effort.

Finally the arm-elf configuration is heading rapidly towards obsolescence so I
would strongly recommend all developers moving towards the arm-eabi port.


-- 

rearnsha at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rearnsha at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WONTFIX


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42100