[Buildroot] [PATCH v10 1/4] Makefile: move LIB_SYMLINK definition to toolchain/helpers.mk

[Buildroot] [PATCH v10 1/4] Makefile: move LIB_SYMLINK definition to toolchain/helpers.mk

[Thomas De Schampheleire]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

Commit 7a6b83a211612ff95a1f5d35b2861ad5655ac8b1 introduced the skeleton
package, which took over the lib32/lib64 -> lib symlink creation from the
main Makefile.
However, the definition of the LIB_SYMLINK variable did not move along, for
no real reason. At that moment, the most logical location for the definition
would be package/skeleton/skeleton.mk.

Given that due to a subsequent commit the definition will also be needed
from toolchain-external, move it instead to toolchain/helpers.mk which is
also conceptually a fine place.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
---
 Makefile                     | 8 --------
 package/skeleton/skeleton.mk | 8 ++++----
 toolchain/helpers.mk         | 8 ++++++++
 3 files changed, 12 insertions(+), 12 deletions(-)

(v10: new patch)

diff --git a/Makefile b/Makefile
index 6bf9864..2e09611 100644
--- a/Makefile
+++ b/Makefile
@@ -501,14 +501,6 @@ world: target-post-image
 $(BUILD_DIR) $(TARGET_DIR) $(HOST_DIR) $(BINARIES_DIR) $(LEGAL_INFO_DIR) $(REDIST_SOURCES_DIR_TARGET) $(REDIST_SOURCES_DIR_HOST):
 	@mkdir -p $@
 
-# We make a symlink lib32->lib or lib64->lib as appropriate
-# MIPS64/n32 requires lib32 even though it's a 64-bit arch.
-ifeq ($(BR2_ARCH_IS_64)$(BR2_MIPS_NABI32),y)
-LIB_SYMLINK = lib64
-else
-LIB_SYMLINK = lib32
-endif
-
 # Populating the staging with the base directories is handled by the skeleton package
 $(STAGING_DIR):
 	@mkdir -p $(STAGING_DIR)
diff --git a/package/skeleton/skeleton.mk b/package/skeleton/skeleton.mk
index 6b5ab79..e2089c7 100644
--- a/package/skeleton/skeleton.mk
+++ b/package/skeleton/skeleton.mk
@@ -82,8 +82,8 @@ define SKELETON_INSTALL_TARGET_CMDS
 		--chmod=u=rwX,go=rX --exclude .empty --exclude '*~' \
 		$(SKELETON_PATH)/ $(TARGET_DIR)/
 	$(call SKELETON_USR_SYMLINKS_OR_DIRS,$(TARGET_DIR))
-	ln -snf lib $(TARGET_DIR)/$(LIB_SYMLINK)
-	ln -snf lib $(TARGET_DIR)/usr/$(LIB_SYMLINK)
+	ln -snf lib $(TARGET_DIR)/$(TOOLCHAIN_LIB_SYMLINK)
+	ln -snf lib $(TARGET_DIR)/usr/$(TOOLCHAIN_LIB_SYMLINK)
 	$(INSTALL) -m 0644 support/misc/target-dir-warning.txt \
 		$(TARGET_DIR_WARNING_FILE)
 endef
@@ -99,8 +99,8 @@ define SKELETON_INSTALL_STAGING_CMDS
 	$(INSTALL) -d -m 0755 $(STAGING_DIR)/usr/sbin
 	$(INSTALL) -d -m 0755 $(STAGING_DIR)/usr/include
 	$(call SKELETON_USR_SYMLINKS_OR_DIRS,$(STAGING_DIR))
-	ln -snf lib $(STAGING_DIR)/$(LIB_SYMLINK)
-	ln -snf lib $(STAGING_DIR)/usr/$(LIB_SYMLINK)
+	ln -snf lib $(STAGING_DIR)/$(TOOLCHAIN_LIB_SYMLINK)
+	ln -snf lib $(STAGING_DIR)/usr/$(TOOLCHAIN_LIB_SYMLINK)
 endef
 
 SKELETON_TARGET_GENERIC_HOSTNAME = $(call qstrip,$(BR2_TARGET_GENERIC_HOSTNAME))
diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
index 70695ee..1d053a2 100644
--- a/toolchain/helpers.mk
+++ b/toolchain/helpers.mk
@@ -1,5 +1,13 @@
 # This Makefile fragment declares toolchain related helper functions.
 
+# We make a symlink lib32->lib or lib64->lib as appropriate
+# MIPS64/n32 requires lib32 even though it's a 64-bit arch.
+ifeq ($(BR2_ARCH_IS_64)$(BR2_MIPS_NABI32),y)
+TOOLCHAIN_LIB_SYMLINK = lib64
+else
+TOOLCHAIN_LIB_SYMLINK = lib32
+endif
+
 # The copy_toolchain_lib_root function copies a toolchain library and
 # its symbolic links from the sysroot directory to the target
 # directory. Note that this function is used both by the external
-- 
2.4.10

[Buildroot] [PATCH v10 2/4] toolchain-external: don't exclude too much lib in sysroot rsync

[Thomas De Schampheleire]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

The copy_toolchain_sysroot helper in toolchain/helpers.mk performs an
rsync of various directories from the extracted external toolchain to the
corresponding directory in staging.

The relevant (simplified) snippet is:
    for i in etc $${ARCH_LIB_DIR} sbin usr usr/$${ARCH_LIB_DIR}; do \
            rsync -au --chmod=u=rwX,go=rX --exclude 'usr/lib/locale' \
                    --exclude lib --exclude lib32 --exclude lib64 \
                    $${ARCH_SYSROOT_DIR}/$$i/ $(STAGING_DIR)/$$i/ ; \
    done ; \

The exclusion logic of lib/lib32/lib64 has been added by commit
5628776c4a4d29d0715633ea463b64cc19e19c5a with the purpose of only copying
the relevant usr/lib* directory from the toolchain to staging, instead of
all. For example, if ARCH_LIB_DIR is 'lib64', then only usr/lib64 would be
copied and usr/lib and usr/lib32 are ignored. It works by ignoring any
lib/lib32/lib64 subdirectory on the rsync of 'usr' and then separately
copying usr/{lib,lib32,lib64} as appropriate. (The exclusion rules only have
impact on the files beneath the main source directory.)

However, on the rsync of 'usr', ANY of the following directories AND files
would be excluded:
    lib/
    lib
    lib32/
    foobar/something/lib/
    something-else/lib64/

while it is only the intention to skip directories directly under usr.

Therefore, add a leading (to restrict the scope to first-level) and trailing
(to restrict to directories) slash to the exclude pattern. From 'man rsync':

    - if the pattern starts with a / then it is anchored to [..] the root of
      the transfer.
    - if the pattern ends with a / then it will only match a directory, not
      a regular file, symlink, or device.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Cc: Samuel Martin <s.martin49@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>

---
 toolchain/helpers.mk | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(v10: new patch)

diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
index 1d053a2..451ab1e 100644
--- a/toolchain/helpers.mk
+++ b/toolchain/helpers.mk
@@ -162,7 +162,8 @@ copy_toolchain_sysroot = \
 	for i in etc $${ARCH_LIB_DIR} sbin usr usr/$${ARCH_LIB_DIR}; do \
 		if [ -d $${ARCH_SYSROOT_DIR}/$$i ] ; then \
 			rsync -au --chmod=u=rwX,go=rX --exclude 'usr/lib/locale' \
-				--exclude lib --exclude lib32 --exclude lib64 \
+				--exclude '/lib/' --exclude '/lib32/' \
+				--exclude '/lib64/' \
 				$${ARCH_SYSROOT_DIR}/$$i/ $(STAGING_DIR)/$$i/ ; \
 		fi ; \
 	done ; \
-- 
2.4.10

[Buildroot] [PATCH v10 3/4] toolchain-external: improve sysroot rsync if ARCH_LIB_DIR != lib/lib32/lib64

[Thomas De Schampheleire]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

The copy_toolchain_sysroot helper in toolchain/helpers.mk performs an
rsync of various directories from the extracted external toolchain to the
corresponding directory in staging.

The relevant (simplified) snippet is:
	for i in etc $${ARCH_LIB_DIR} sbin usr usr/$${ARCH_LIB_DIR}; do \
		rsync -au --chmod=u=rwX,go=rX --exclude 'usr/lib/locale' \
			--exclude '/lib/' --exclude '/lib32/' \
			--exclude '/lib64/' \
			$${ARCH_SYSROOT_DIR}/$$i/ $(STAGING_DIR)/$$i/ ; \
	done ; \

The exclusion logic of lib/lib32/lib64 has originally been added by commit
5628776c4a4d29d0715633ea463b64cc19e19c5a with the purpose of only copying
the relevant usr/lib* directory from the toolchain to staging, instead of
all. For example, if ARCH_LIB_DIR is 'lib64', then only usr/lib64 would be
copied and usr/lib and usr/lib32 are ignored. It works by ignoring any
lib/lib32/lib64 subdirectory on the rsync of 'usr' and then separately
copying usr/{lib,lib32,lib64} as appropriate. (The exclusion rules only have
impact on the files beneath the main source directory.)

However, ARCH_LIB_DIR can take other values than (lib, lib32, lib64), for
example lib32-fp or lib64-fp (Octeon III toolchain with -march=octeon3). In
the existing code, the rsync for 'usr' would then already copy these lib
directories, and the next rsync for 'usr/$${ARCH_LIB_DIR}' does nothing.

By itself, this is not a very big problem: the staging directory simply has
some extra directories. However, a subsequent patch will create a staging
symlink from $${ARCH_LIB_DIR} to lib. The first rsync would then overwrite
that symlink with the real directory usr/$${ARCH_LIB_DIR} from the
toolchain, which is not correct.

Assuming the patch that creates the symlink ARCH_LIB_DIR->lib is applied,
the original situation after 'make clean toolchain' with an
ARCH_LIB_DIR=lib32-fp is:

$ ls -ld output/staging/{,usr/}lib* output/target/{usr/,}lib*
drwxr-xr-x 2  4096 May 26  2015 output/staging/lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/staging/lib32 -> lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/staging/lib32-fp -> lib
drwxr-xr-x 2  4096 Jan 20 13:47 output/staging/usr/lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/staging/usr/lib32 -> lib
drwxr-xr-x 4  4096 May 26  2015 output/staging/usr/lib32-fp
drwxr-xr-x 4  4096 May 26  2015 output/staging/usr/lib64-fp
drwxr-xr-x 4  4096 May 26  2015 output/staging/usr/libexec
drwxr-xr-x 3  4096 May 26  2015 output/staging/usr/libexec32
drwxr-xr-x 3  4096 May 26  2015 output/staging/usr/libexec32-fp
drwxr-xr-x 3  4096 May 26  2015 output/staging/usr/libexec64-fp
drwxr-xr-x 2  4096 Jan 20 13:48 output/target/lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/target/lib32 -> lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/target/lib32-fp -> lib
drwxr-xr-x 2  4096 Jan 20 13:48 output/target/usr/lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/target/usr/lib32 -> lib
lrwxrwxrwx 1     3 Jan 20 13:47 output/target/usr/lib32-fp -> lib

Notice how usr/lib32-fp is not a symlink but a directory, and the presence
of an unnecessary directory usr/lib64-fp.

This patch improves the rsync exclusion rules by excluding any lib*
directory on the first rsync. As this would also exclude any
libexec/libexec32/... directory, explicitly include them first (first match
takes precedence). This (as is already the case today) results in more
usr/libexec* directories than needed, but it is not touched by this patch.

With the fix applied, the situation becomes:

drwxr-xr-x 2 4096 May 26  2015 output/staging/lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/staging/lib32 -> lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/staging/lib32-fp -> lib
drwxr-xr-x 4 4096 May 26  2015 output/staging/usr/lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/staging/usr/lib32 -> lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/staging/usr/lib32-fp -> lib
drwxr-xr-x 4 4096 May 26  2015 output/staging/usr/libexec
drwxr-xr-x 3 4096 May 26  2015 output/staging/usr/libexec32
drwxr-xr-x 3 4096 May 26  2015 output/staging/usr/libexec32-fp
drwxr-xr-x 3 4096 May 26  2015 output/staging/usr/libexec64-fp
drwxr-xr-x 2 4096 Jan 20 14:27 output/target/lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/target/lib32 -> lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/target/lib32-fp -> lib
drwxr-xr-x 2 4096 Jan 20 14:27 output/target/usr/lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/target/usr/lib32 -> lib
lrwxrwxrwx 1    3 Jan 20 14:27 output/target/usr/lib32-fp -> lib

For cases where ARCH_LIB_DIR is one of lib, lib32 or lib64 this fix
makes no difference, and likewise for internal toolchains.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Cc: Samuel Martin <s.martin49@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>

---
 toolchain/helpers.mk | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(v10: new patch)

diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
index 451ab1e..aa2adbd 100644
--- a/toolchain/helpers.mk
+++ b/toolchain/helpers.mk
@@ -162,8 +162,7 @@ copy_toolchain_sysroot = \
 	for i in etc $${ARCH_LIB_DIR} sbin usr usr/$${ARCH_LIB_DIR}; do \
 		if [ -d $${ARCH_SYSROOT_DIR}/$$i ] ; then \
 			rsync -au --chmod=u=rwX,go=rX --exclude 'usr/lib/locale' \
-				--exclude '/lib/' --exclude '/lib32/' \
-				--exclude '/lib64/' \
+				--include '/libexec*/' --exclude '/lib*/' \
 				$${ARCH_SYSROOT_DIR}/$$i/ $(STAGING_DIR)/$$i/ ; \
 		fi ; \
 	done ; \
-- 
2.4.10

[Buildroot] [PATCH v10 4/4] toolchain-external: create symlink ARCH_LIB_DIR->lib

[Thomas De Schampheleire]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

Currently, following symbolic links are created in both target and
staging directories:
- lib(32|64) --> lib
- usr/lib(32|64) --> lib

The decision for lib32 or lib64 is based on the target architecture
configuration in buildroot (BR2_ARCH_IS_64).

In at least one case this is not correct: when building for a Cavium Octeon
III processor using the toolchain from the Cavium Networks SDK, and
specifying -march=octeon3 in BR2_TARGET_OPTIMIZATION, libraries are expected
in directory 'lib32-fp' rather than 'lib32' (ABI=n32; likewise for
lib64-fp in case of ABI=n64)

More generally the correct symbolic link is from (usr/)${ARCH_LIB_DIR}->lib.
However, feedback from Arnout Vandecappelle is that there are packages that
do depend on the lib32/lib64 symlink, even if ARCH_LIB_DIR is different.
Hence, these links must be kept.

Fix the problem as follows:
- For internal toolchains: no change
- For external toolchains: create a symlink ARCH_LIB_DIR->lib if
  ARCH_LIB_DIR is different from lib/lib32/lib64.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Cc: "Yann E. Morin" <yann.morin.1998@free.fr>
Cc: Romain Naour <romain.naour@gmail.com>
Cc: Peter Korsgaard <peter@korsgaard.com>

---
 toolchain/toolchain-external/toolchain-external.mk | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)

v10:
- simplify after realization that skeleton symlink creation can be kept
  (thanks Thomas Petazzoni for noticing this)
v9:
- remove redundant mkdir's (handled by skeleton) (Yann)
v8:
- use helper only for external toolchain and incorporate ARCH_LIB_DIR
  definition (Arnout)
- keep lib32/lib64->lib symlink anyway
v7: rebase
v6: rebase only
v5:
- move internal toolchain logic into gcc-initial.mk
- also silence the internal toolchain link steps with $(Q)
v4:
- merge both helpers into one
- remove the separate target for the internal toolchain and hook into
  gcc-initial
- re-add deleted comment about MIPS64/n32
v3:
- update commit message wrapping
- change dependency on $(BUILD_DIR) to a order-only dependency
v2:
- fix 'lib32-fp' leftover in toolchain-buildroot
- silence commands creating symlink with $(Q)
- fix case where ARCH_LIB_DIR is 'lib'

Note: in output/staging/usr/ there would still be more directories than I
think are really necessary. This behavior is not changed by this patch, it
was already present before.
For example, with the mentioned Octeon III toolchain, output/staging/usr/
contains:
    bin      bin32      bin32-fp      bin64-fp,
    lib      lib32      lib32-fp      lib64-fp
    libexec  libexec32  libexec32-fp  libexec64-fp
    sbin     sbin32     sbin32-fp     sbin64-fp

where bin/lib/libexec/sbin seem to be the 64-bit equivalents of
bin32/lib32/libexec32/sbin32.
This is related to the behavior of copy_toolchain_sysroot in
toolchain/helpers.mk. It already attempts to filter out the unnecessary lib*
directories, but does not care about any bin/sbin/libexec directories.
As this poses no known problem and is not impacted by this patch, I make no
attempt to change it.

diff --git a/toolchain/toolchain-external/toolchain-external.mk b/toolchain/toolchain-external/toolchain-external.mk
index ddefd01..10f1edc 100644
--- a/toolchain/toolchain-external/toolchain-external.mk
+++ b/toolchain/toolchain-external/toolchain-external.mk
@@ -517,6 +517,27 @@ endef
 TOOLCHAIN_EXTERNAL_POST_INSTALL_STAGING_HOOKS += TOOLCHAIN_EXTERNAL_MUSL_LD_LINK
 endif
 
+# Create a symlink from (usr/)$(ARCH_LIB_DIR) to lib.
+# Note: the skeleton package additionally creates lib32->lib or lib64->lib
+# (as appropriate)
+#
+# $1: destination directory (TARGET_DIR / STAGING_DIR)
+create_lib_symlinks = \
+       $(Q)DESTDIR="$(strip $1)" ; \
+       ARCH_LIB_DIR="$(call toolchain_find_libdir,$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
+       if [ "$${ARCH_LIB_DIR}" != "lib" -a "$${ARCH_LIB_DIR}" != "$(SKELETON_LIB_SYMLINK)" ]; then \
+               ln -snf lib "$${DESTDIR}/$${ARCH_LIB_DIR}" ; \
+               ln -snf lib "$${DESTDIR}/usr/$${ARCH_LIB_DIR}" ; \
+       fi
+
+define TOOLCHAIN_EXTERNAL_CREATE_STAGING_LIB_SYMLINK
+       $(call create_lib_symlinks,$(STAGING_DIR))
+endef
+
+define TOOLCHAIN_EXTERNAL_CREATE_TARGET_LIB_SYMLINK
+       $(call create_lib_symlinks,$(TARGET_DIR))
+endef
+
 # Integration of the toolchain into Buildroot: find the main sysroot
 # and the variant-specific sysroot, then copy the needed libraries to
 # the $(TARGET_DIR) and copy the whole sysroot (libraries and headers)
@@ -732,6 +753,7 @@ endef
 TOOLCHAIN_EXTERNAL_BUILD_CMDS = $(TOOLCHAIN_BUILD_WRAPPER)
 
 define TOOLCHAIN_EXTERNAL_INSTALL_STAGING_CMDS
+	$(TOOLCHAIN_EXTERNAL_CREATE_STAGING_LIB_SYMLINK)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_SYSROOT_LIBS)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_WRAPPER)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_GDBINIT)
@@ -741,6 +763,7 @@ endef
 # and the target directory, we do everything within the
 # install-staging step, arbitrarily.
 define TOOLCHAIN_EXTERNAL_INSTALL_TARGET_CMDS
+	$(TOOLCHAIN_EXTERNAL_CREATE_TARGET_LIB_SYMLINK)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_TARGET_LIBS)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_BFIN_FDPIC)
 	$(TOOLCHAIN_EXTERNAL_INSTALL_BFIN_FLAT)
-- 
2.4.10

[Buildroot] [PATCH v10 4/4] toolchain-external: create symlink ARCH_LIB_DIR->lib

[Thomas Petazzoni]

Dear Thomas De Schampheleire,

On Wed, 20 Jan 2016 16:09:07 +0100, Thomas De Schampheleire wrote:

> +       ARCH_LIB_DIR="$(call toolchain_find_libdir,$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
> +       if [ "$${ARCH_LIB_DIR}" != "lib" -a "$${ARCH_LIB_DIR}" != "$(SKELETON_LIB_SYMLINK)" ]; then \

Where is SKELETON_LIB_SYMLINK defined? Shouldn't this be
TOOLCHAIN_LIB_SYMLINK ?

Or better, can we indeed name the variable SKELETON_LIB_SYMLINK, have
it under skeleton.mk, and replace this test by something that simply
tests if ARCH_LIB_DIR exists or not. If it exists (i.e it's the lib/
directory, or one of the lib32/ or lib64/ symlinks), there is nothing
to do, otherwise you need to create the symlinks.

Best regards,

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

[Buildroot] [PATCH v10 4/4] toolchain-external: create symlink ARCH_LIB_DIR->lib

[Thomas De Schampheleire]

On Wed, Jan 20, 2016 at 4:24 PM, Thomas Petazzoni
<thomas.petazzoni@free-electrons.com> wrote:
> Dear Thomas De Schampheleire,
>
> On Wed, 20 Jan 2016 16:09:07 +0100, Thomas De Schampheleire wrote:
>
>> +       ARCH_LIB_DIR="$(call toolchain_find_libdir,$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
>> +       if [ "$${ARCH_LIB_DIR}" != "lib" -a "$${ARCH_LIB_DIR}" != "$(SKELETON_LIB_SYMLINK)" ]; then \
>
> Where is SKELETON_LIB_SYMLINK defined? Shouldn't this be
> TOOLCHAIN_LIB_SYMLINK ?

This is indeed an error.

>
> Or better, can we indeed name the variable SKELETON_LIB_SYMLINK, have
> it under skeleton.mk, and replace this test by something that simply
> tests if ARCH_LIB_DIR exists or not. If it exists (i.e it's the lib/
> directory, or one of the lib32/ or lib64/ symlinks), there is nothing
> to do, otherwise you need to create the symlinks.

Yes, that can be done, I will resubmit.
Thanks for your feedback,
Thomas