[Bug web/62211] New: ./configure --with-float= and ARM

[Bug web/62211] New: ./configure --with-float= and ARM

[dilyan.palauzov at aegee dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62211

            Bug ID: 62211
           Summary: ./configure --with-float= and ARM
           Product: gcc
           Version: 4.9.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: web
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dilyan.palauzov at aegee dot org

At https://gcc.gnu.org/install/configure.html is written:

Options specification

--with-fpu=type
--with-float=type
  These configure options provide default values for the -mfpu= option and for
-mhard-float or -msoft-float.

I want to configure for ARM.  In the gcc manual, node 3.1 Option Summary under
_ARM Options_ is mentioned the option -mfloat-abi= but -m(hard,sort)-float are
not mentioned.

In node 3.17.4 ARM Options is mentioned, that -mfloat-abi can be hard, soft or
softfp.

Does ./configure-ing gcc --with-float=X lead to defaulting the -mfloat-abi
option later, when gcc is not called?  In such a case, the documentation for
configuring gcc shall mention, that --with-float=type on ARM has no impact on
-msoft-float or -mhard-float, but on -mfloat-abi .

The documentation of GCC does mention neither -mhard-float nor -msoft-float as
general options nor as ARM-specific options, so I conclude that these are not
permitted.

However, the documentation of -mfpu= , where the ARM options are described,
mentions:

     If '-msoft-float' is specified this specifies the format of floating-point
values.


So apparently, -msoft-float can be passed, when gcc produces ARM-code.

Please clarify in the gcc manual if -msoft-float is the same as
-mfloat-abi=soft, if -mhard-float is the same as -mfloat-abi=hard and if these,
including -mfloag-abu=softfp are impacted by ./configure --with-float .

[Bug web/62211] ./configure --with-float= and ARM

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62211

--- Comment #1 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
-m{soft,hard}-float for arm should be considered deprecated (we try to support
them by mapping them onto the -mfloat-abi option), and deliberately no-longer
document them.  

Rather than clarifying what they do, the references elsewhere should be cleaned
up to use -mfloat-abi.  Specifically, in this case, the reference to
-msoft-float should be changed to -mfloat-abi=soft.

[Bug web/62211] ./configure --with-float= and ARM

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62211

Ramana Radhakrishnan <ramana at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |documentation
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-01-16
                 CC|                            |ramana at gcc dot gnu.org
   Target Milestone|---                         |5.0
     Ever confirmed|0                           |1

[Bug web/62211] ./configure --with-float= and ARM

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62211

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|5.0                         |5.2

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 5.1 has been released.

[Bug web/62211] ./configure --with-float= and ARM

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62211

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|5.2                         |5.3

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 5.2 is being released, adjusting target milestone to 5.3.