Commit 65473afe authored by Thomas Petazzoni's avatar Thomas Petazzoni
Browse files

uclibc: adapt thread implementation selection to uClibc-ng 

uClibc-ng does not support linuxthreads or linuxthreads.old on
architectures that have NPTL support. This creates another complicated
dependency: dependeing on the uClibc version being used, not the same
thread implementations are available.

In order to handle this situation, this patch introduces three hidden
booleans:

 - BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS
 - BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD
 - BR2_UCLIBC_VERSION_SUPPORTS_NPTL

They are selected by the different uClibc versions, depending on which
thread implementation they support on the different architectures.

Then, the choice of the thread implementation can rely on those
booleans to know if a given thread implementation is available in the
current architecture / uClibc version selection.

This makes sure that unusable thread implementation do not get
selected, therefore fixing build issues such as:

  http://autobuild.buildroot.org/results/89e/89e423bee040cbce3e82cd89f1191efaac490c0d/



The support table is as follows (only taking into account
architectures that allow the selection of
BR2_TOOLCHAIN_BUILDROOT_UCLIBC, other architectures are not
considered) :

             ----uclibc----   uclibc-xtensa-   --uclibc-arc--  --uclibc-ng---
             LT LT.old NPTL   LT LT.old NPTL   LT LT.old NPTL  LT LT.old NPTL
arc(le|eb)                                      y   y     n    n    n     n (1)
arm(eb)      y    y     y                                      n    y     y (2)
bfin         n    y     n                                      y    y     n
i386         y    y     y                                      n    n     y (3)
m68k         y    y     y                                      y    y     n
mips(64)(el) y    y     y                                      n    n     y
powerpc      y    y     y                                      n    n     y
sh           y    y     y                                      n    n     y
sparc        y    y     y                                      n    n     y
xtensa                        n    y     n                     n    n     y
x86_64       y    y     y                                      n    n     y

  (1) : uclibc-ng only has NPTL support for ARC but it requires a more
        recent compiler version that hasn't been officially released
        by Synopsys.

  (2) : the general idea of uclibc-ng is to only support NPTL on
        architectures where it is available. However, in order to
        support ARM noMMU platforms, LT.old support has been kept on
        ARM.

  (3) : except i386 itself, which doesn't have what's needed for NPTL
        support. i386 is simply not supported by uclibc-ng basically.

Signed-off-by: default avatarThomas Petazzoni <thomas.petazzoni@free-electrons.com>
parent 272bb6b2

package/uclibc/Config.in

+33 −10
Original line number Diff line number Diff line
@@ -7,6 +7,15 @@ config BR2_PACKAGE_UCLIBC 


comment "uClibc Options"



config BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS

       bool



config BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD

       bool



config BR2_UCLIBC_VERSION_SUPPORTS_NPTL

       bool



choice

	prompt "uClibc C library Version"

	default BR2_UCLIBC_VERSION_0_9_33
@@ -15,21 +24,39 @@ choice 


	config BR2_UCLIBC_VERSION_0_9_33

		bool "uClibc 0.9.33.x"

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS \

		       if !BR2_bfin

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD

		select BR2_UCLIBC_VERSION_SUPPORTS_NPTL \

		       if !BR2_bfin && !BR2_x86_i386

		depends on !(BR2_arc || BR2_xtensa)



	config BR2_UCLIBC_VERSION_ARC_GIT

		bool "uClibc Git ARC"

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD

		depends on BR2_arc



	config BR2_UCLIBC_NG_VERSION_1_0_0

		bool "uClibc-ng 1.0.0"

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS \

		       if BR2_bfin || BR2_m68k

		select BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD \

		       if BR2_bfin || BR2_m68k || BR2_arm || BR2_armeb

		select BR2_UCLIBC_VERSION_SUPPORTS_NPTL \

		       if !BR2_arc && !BR2_bfin && !BR2_m68k && !BR2_x86_i386



	config BR2_UCLIBC_VERSION_XTENSA_GIT

		bool "uClibc Git Xtensa"

		depends on BR2_xtensa

		select BR2_UCLIBC_SUPPORTS_LINUXTHREADS_OLD



	config BR2_UCLIBC_VERSION_SNAPSHOT

		bool "daily snapshot"

		select BR2_UCLIBC_SUPPORTS_LINUXTHREADS if !BR2_bfin && !BR2_xtensa

		select BR2_UCLIBC_SUPPORTS_LINUXTHREADS_OLD

		select BR2_UCLIBC_VERSION_SUPPORTS_NPTL \

		       if !BR2_bfin && !BR2_x86_i386 && !BR2_xtensa

		depends on !(BR2_arc)



endchoice
@@ -101,8 +128,9 @@ config BR2_TOOLCHAIN_BUILDROOT_LOCALE 


choice

	prompt "Thread library implementation"

	default BR2_PTHREADS_NATIVE if !BR2_xtensa

	default BR2_PTHREADS_OLD

	default BR2_PTHREADS_NATIVE if BR2_UCLIBC_VERSION_SUPPORTS_NPTL

	default BR2_PTHREADS_OLD if BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD

	default BR2_PTHREADS if BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS

	help

	  Use this option to select the thread library implementation

	  that should be used in your toolchain. Not all thread
@@ -115,24 +143,19 @@ choice 


	config BR2_PTHREADS

		bool "linuxthreads"

		depends on !BR2_bfin

		depends on !BR2_xtensa

		select BR2_TOOLCHAIN_HAS_THREADS

		depends on BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS



	config BR2_PTHREADS_OLD

		bool "linuxthreads (stable/old)"

		select BR2_TOOLCHAIN_HAS_THREADS

		depends on BR2_UCLIBC_VERSION_SUPPORTS_LINUXTHREADS_OLD



	config BR2_PTHREADS_NATIVE

		bool "Native POSIX Threading (NPTL)"

		select BR2_TOOLCHAIN_HAS_THREADS

		select BR2_TOOLCHAIN_HAS_THREADS_NPTL

		depends on !BR2_arc

		depends on !BR2_bfin

		# There is NPTL support for Xtensa in uClibc-ng, but

		# not in the main uClibc repository.

		depends on !BR2_xtensa || !BR2_UCLIBC_VERSION_XTENSA_GIT

		depends on !BR2_x86_i386

		depends on BR2_UCLIBC_VERSION_SUPPORTS_NPTL

endchoice



config BR2_PTHREAD_DEBUG