config/arch/arm.in.2
author Bryan Hundven <bryanhundven@gmail.com>
Sun Jun 26 03:26:54 2011 -0700 (2011-06-26)
changeset 2515 364b06df9e3a
parent 2111 5f4dbeb370e1
child 2788 b6faa28e76e0
permissions -rw-r--r--
glibc: Refactor startfiles/headers into do_libc_backend()

Refactor the contents of 'do_libc_start_files()' and 'do_libc()' into a
parameterized 'do_libc_backend()'. 'do_libc_start_files()' and 'do_libc()'
call 'do_libc_backend()' with either 'libc_mode=startfiles' or
'libc_mode=final' (respectively) so that the startfiles/headers and
the final libc builds are configured and built with the same options.

One example of where this is needed is when building a mips toolchain.
Previously, if you were building an n32 toolchain, you wouldn't have
noticed an issue, because if '-mabi' is not in CFLAGS, n32 is the
default:

http://sourceware.org/git/?p=glibc-ports.git;a=blob;f=sysdeps/mips/preconfigure;hb=HEAD

But when trying to build an o32 or n64 toolchain the build would
have failed. This is because (e)glibc expects "-mabi={o32,n32,n64}" to be
in CFLAGS, but was not previously provided in 'do_libc_start_files()'.
The build failure would happen in the shared-core gcc when it tries to
configure an n64 or o32 gcc with an n32 libc.

A simpler solution would have been to just add TARGET_CFLAGS to configure
in 'do_libc_start_files()', but this way makes configure and make
consistent for both steps.

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
     1 # ARM specific configuration file
     2 
     3 config ARCH_ARM_MODE
     4     string
     5     default "arm"   if ARCH_ARM_MODE_ARM
     6     default "thumb" if ARCH_ARM_MODE_THUMB
     7 
     8 choice
     9     bool
    10     prompt "Default instruction set mode"
    11     default ARCH_ARM_MODE_ARM
    12 
    13 config ARCH_ARM_MODE_ARM
    14     bool
    15     prompt "arm"
    16     help
    17       Defaults to emitting instructions in the ARM mode.
    18 
    19 config ARCH_ARM_MODE_THUMB
    20     bool
    21     prompt "thumb (EXPERIMENTAL)"
    22     depends on EXPERIMENTAL
    23     help
    24       Defaults to emitting instructions in the THUMB mode.
    25 
    26 endchoice
    27 
    28 config ARCH_ARM_INTERWORKING
    29     bool
    30     prompt "Use Thumb-interworking (READ HELP)"
    31     depends on EXPERIMENTAL
    32     help
    33       Excerpt from the gcc manual:
    34       
    35       > Generate code which supports calling between the ARM and Thumb
    36       > instruction sets. Without this option the two instruction sets
    37       > cannot be reliably used inside one program. The default is
    38       > [not to use interwork], since slightly larger code is generated
    39       > when [interwork] is specified.
    40 
    41 config ARCH_ARM_EABI
    42     bool
    43     prompt "Use EABI"
    44     default y
    45     help
    46       Set up the toolchain so that it generates EABI-compliant binaries.
    47 
    48 config ARCH_ARM_ABI_OK
    49     bool
    50     default y
    51     depends on ! ARCH_ARM_EABI
    52     select ARCH_SUPPORT_ABI