[Buildroot] Blackfin Buildroot toolchain issue

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear Gustavo Zacarias,

On Tue, 17 Mar 2015 12:08:16 -0300, Gustavo Zacarias wrote:

> There's this as well:
> https://bugs.busybox.net/show_bug.cgi?id=7921
> Which basically boils down to uclibc NPTL requiring TLS.
> I'll check for space savings to see if it makes sense for it to even be
> an option.

I think it might make sense to keep it a blind option so that we don't
do --enable-tls on architectures that don't have TLS support at all (if
that even exists).

I have something like that in one of my branches:

commit 2ea50f3887747d6b72d6b133806d8b3ff995fe4a
Author: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Date:   Wed Mar 11 23:05:00 2015 +0100

    gcc: make TLS option a blind option
    
    The current BR2_GCC_ENABLE_TLS option can lead users to create a
    non-working configuration: if they choose uClibc with NPTL and disable
    TLS support. This is bug #7921.
    
    Since TLS support is really an internal thing, it doesn't make a lot
    of sense to have a visible option for this. Therefore, this commit
    turns it to a blind option: TLS support is enabled in the compiler if
    glibc, eglibc or uClibc NPTL are used, and is disabled otherwise.
    
    Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

diff --git a/package/gcc/Config.in.host b/package/gcc/Config.in.host
index 1a5281c..120d4d8 100644
--- a/package/gcc/Config.in.host
+++ b/package/gcc/Config.in.host
@@ -109,12 +109,9 @@ config BR2_TOOLCHAIN_BUILDROOT_CXX
          your target system.
 
 config BR2_GCC_ENABLE_TLS
-       bool "Enable compiler tls support" if BR2_TOOLCHAIN_BUILDROOT_UCLIBC
+       bool
        default y
        depends on BR2_PTHREADS_NATIVE || BR2_TOOLCHAIN_BUILDROOT_EGLIBC || BR2_TOOLCHAIN_BUILDROOT_GLIBC
-       help
-         Enable the compiler to generate code for accessing
-         thread local storage variables
 
 config BR2_GCC_ENABLE_LTO
        bool "Enable compiler link-time-optimization support"


Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com