In GCC6 the compiler was made smarter to omit the flag
-fdebug-prefix-map from the DWARF DW_AT_producer section[1]. That flag
contains the absolute path '$(BASE_DIR)' which breaks reproducibility.
Prior to GCC6 however, the only way to omit the flag is to use
-gno-record-gcc-switches which omits all flags.
[1] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=266cc0c181549c2fb6b50f8f26213cdc89101026
Signed-off-by: Brandon Maier <brandon.maier@rockwellcollins.com>
[Arnout: invert condition to ifeq (,) instead of ifneq (,y)]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
In GCC8 the flag -ffile-prefix-map handles cleaning up both the __FILE__
macros and the debug info paths. In GCC7 or below we are manually
handling the __FILE__ macros, but not debug info paths. Use
-fdebug-prefix-map to clean them up. This option exists since GCC 4.3.0,
which is our minimal supported GCC version.
See for more detail: https://reproducible-builds.org/docs/build-path/
Signed-off-by: Brandon Maier <brandon.maier@rockwellcollins.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
When using precompiled headers, changing any macros defined on the
command line will invalidate the precompiled header. With
toolchain-wrapper adding __DATE__ and __TIME__, any commits to Buildroot
will invalidate incremental builds regardless of whether the precompiled
header actually uses those values (affecting _OVERRIDE_SRCDIR).
GCC-7 and later support SOURCE_DATE_EPOCH and use it to define __DATE__
and __TIME__ internally, avoiding any impact on precompiled headers.
Disable the custom handling in toolchain-wrapper if GCC is version 7 or
newer.
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Many tools use __FILE__ or __BASE_FILE__ for debugging and both
capture the build path. This results in non-reproducible images when
building in different directories.
If the config uses GCC 8 or above, we use -ffile-prefix-map=old=new
and let gcc take care of the path remapping in __FILE__. Since GCC
versions before v8 did not have this feature, we use an empty string
in that case, and disable the builtin-macro-redefined warning which
would otherwise trigger and cause build issues with -Werror.
Signed-off-by: Atharva Lele <itsatharva@gmail.com>
[Thomas:
- as suggested by Arnout, use the empty string for the __FILE__ and
__BASE_FILE__ value
- as suggested by Romain, also handle __BASE_FILE__ in addition to
__FILE__
- pass -Wno-builtin-macro-redefined to avoid build errors when
-Werror is passed]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Build ID is added to binaries at link time. Building in different
output directories causes some packages to have different Build IDs,
thus resulting in non-reproducibility.
Adding "-Wl,--build-id=none" fixes this issue by disabling setting of
Build ID.
Diffoscope output for Build ID issue:
https://gitlab.com/snippets/1886180/raw
After this patch, build is reproducible - i.e. diffoscope does not
produce any output.
Signed-off-by: Atharva Lele <itsatharva@gmail.com>
Reviewed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
In commit 7484c1c3b8 (toolchain/toolchain-wrapper: add BR2_RELRO_),
we added the PIC/PIE flags, but based on the RELRO_FULL condition.
It is however totally possible to do a PIC/PIE executable without
RELRO_FULL, as it is also valid to do a PIC/PIE build with RELRO_PARTIAL.
Add a new option that now governs the PIC/PIE flags.
Note: it is unknown if RELRO_FULL really needs PIC/PIE or not, so we
keep the current situation, where RELRO-FULL forces PIC/PIE compilation.
Decoupling can come later from an interested party.
Signed-off-by: "Yann E. MORIN" <yann.morin@orange.com>
Cc: Matt Weber <matthew.weber@rockwellcollins.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Reviewed-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Currently, we repeat all the SSP level selection deep down to the
toolchain wrapper itself, where we eventually translate it to the
actual SSP option to use. This is a bit redundant.
Additionally, we will want to check that the toolchain actually
supports that option (for those toolchain where it was backported).
So, move the translation into kconfig, and add the qstrip'ed value
to the additional flags passed to the wrapper. Add it before
user-supplied opitons, to keep the previous behaviour (and allow
anyone crazy-enough to override it with BR2_TARGET_OPTIMIZATION).
Signed-off-by: "Yann E. MORIN" <yann.morin@orange.com>
Cc: Matt Weber <matthew.weber@rockwellcollins.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Reviewed-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Currently, we pass the user-supplied so-called target optimisation flags
to the wrapper.
We're going to have additional such CFLAGS to pass, so push-back the
formatting loop to quote the options at the last moment.
Reported-by: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: "Yann E. MORIN" <yann.morin@orange.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Migrate the stack protection flag management into the wrapper.
Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
The RELRO/PIE flags are currently passed via CFLAGS/LDFLAGS and this patch
proposes moving them to the toolchain wrapper.
(1) The flags should _always_ be passed, without leaving the possibility
for any package to ignore them. I.e, when BR2_RELRO_FULL=y is used
in a build, all executables should be built PIE. Passing those
options through the wrapper ensures they are used during the build
of all packages.
(2) Some options are incompatible with -fPIE. For example, when
building object files for a shared libraries, -fPIC is used, and
-fPIE shouldn't be used in combination with -fPIE. Similarly, -r
or -static are directly incompatible as they are different link
time behaviors then the intent of PIE. Passing those options
through the wrapper allows to add some "smart" logic to only pass
-fPIE/-pie when relevant.
(3) Some toolchain, kernel and bootloader packages may want to
explicitly disable PIE in a build where the rest of the userspace
has intentionally enabled it. The wrapper provides an option
to key on the -fno-pie/-no-pie and bypass the appending of RELRO
flags.
The current Kernel and U-boot source trees include this option.
8438ee76b06ace36e19a
If using PIE with a older Kernel and/or U-boot version, a backport of these
changes might be required. However this patchset also uses the
__KERNEL__ and __UBOOT__ defines as a way to disable PIE.
NOTE: The current implementation via CFLAGS/LDFLAGS has caused some
build time failures as the conditional logic doesn't yet exist in
Buildroot:
https://bugs.busybox.net/show_bug.cgi?id=11206https://bugs.busybox.net/show_bug.cgi?id=11321
Good summary of the most common build failures related to
enabling pie: https://wiki.ubuntu.com/SecurityTeam/PIE
[Peter: minor cleanups]
Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Since gcc 4.6, GCC deprecated -mfused-madd, -ffp-contract=off should
be used for the Xburst workaround.
Tested with the MIPS Sourcery 2011.03 toolchain (based on gcc 4.5),
the toolchain wrapper uses -mno-fused-madd, as expected:
$ BR2_DEBUG_WRAPPER=2 ./output/host/bin/mips-linux-gnu-gcc -o toto toto.c
Toolchain wrapper executing:
'/home/thomas/toolchains/mips-2011.03/bin/mips-linux-gnu-gcc'
'--sysroot'
'/home/thomas/projets/buildroot/output/host/mipsel-buildroot-linux-gnu/sysroot'
'-mabi=32'
'-msoft-float'
'-mno-fused-madd'
'-EL'
'-march=mips32r2'
'-o'
'toto'
'toto.c'
And with the MIPS Sourcery 2012.09 toolchain (based on gcc 4.7), the
toolchain wrapper uses -ffp-contract=off, as expected:
$ BR2_DEBUG_WRAPPER=2 ./output/host/bin/mips-linux-gnu-gcc -o toto toto.c
Toolchain wrapper executing:
'/home/thomas/toolchains/mips-2012.09/bin/mips-linux-gnu-gcc'
'--sysroot'
'/home/thomas/projets/buildroot/output/host/mipsel-buildroot-linux-gnu/sysroot'
'-mabi=32'
'-msoft-float'
'-ffp-contract=off'
'-EL'
'-march=mips32r2'
'-o'
'toto'
'toto.c'
Fixes the ci20_defconfig build:
https://gitlab.com/buildroot.org/buildroot/-/jobs/60303132
Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
[Thomas: rework to continue supporting pre-gcc-4.6 toolchains, extend
the commit log after doing more testing.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
The header of the .mk file fits in one line, so rearrange it to be
similar to a header from a package.
Signed-off-by: Ricardo Martincoski <ricardo.martincoski@gmail.com>
Cc: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Since things are no longer installed in $(HOST_DIR)/usr, the callers
should also not refer to it.
This is a mechanical change with
git grep -l '$(HOST_DIR)/usr/bin' | xargs sed -i 's%$(HOST_DIR)/usr/bin%$(HOST_DIR)/bin%g'
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
The Ingenic XBurst is a MIPS32R2 microprocessor.
It has a bug in the FPU that can generate incorrect results in certain
cases. The problem shows up when you have several fused madd
instructions in sequence with dependant operands.
Using the -mno-fused-madd option prevents gcc from emitting these
instructions. This patch adds changes to the toolchain wrapper to use
that option.
Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
toolchain-wrapper was not reinstalled. So rules toolchain-external-reinstall,
gcc-initial-reinstall, gcc-final-reinstall didn't work as expected.
In add, normalize variable name: s/TOOLCHAIN_BUILD_WRAPPER/TOOLCHAIN_WRAPPER_BUILD/
Signed-off-by: Jérôme Pouiller <jezz@sysmic.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
In Makefile, the comma ',' is used to separate the arguments passed to
functions, so we should not be allowed to use straight commas in strings
we want to expand.
For the toolchain wrapper, we need to transform a list:
-mfoo -mbar -mbuz
into something acceptable for a C array assignment:
"-mfoo", "-mbar", "-mbuz",
So, we use a $(foreach ...) loop for that. However, we do have a
straight comma in there.
It does not cause any issue in practice, since $(foreach) is a make
builtin function that accepts three and only three parameters.
However, this is not sane.
Change the straight comma to the usual $(comma) expansion, like we would
do for a call to any other function.
At the same time, make the code a bit easier to read, by first creating
the transformed list, and then creating the define.
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Arnout Vandecappelle <arnout@mind.be>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Tested-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
The Intel X1000 is the Pentium class microprocessor that ships with
Galileo Gen 1/2. This patch adds changes to arch and toolchain-wrapper
to omit the lock prefix for the X1000.
[Thomas: tweak commit log and Config.in help text.]
Signed-off-by: Ray Kinsella <ray.kinsella@intel.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
When building in a different output directory than the original build,
there will currently be a lot of ccache misses because in many cases
there is some -I/... absolute path in the compilation. Ccache has an
option CCACHE_BASEDIR to substitute absolute paths with relative paths,
so they wil be the same in the hash (and in the output).
Since there are some disadvantages to this path rewriting, it is made
optional as BR2_CCACHE_USE_BASEDIR. It defaults to y because the
usefulness of ccache is severely reduced without this option.
In addition to CCACHE_BASEDIR, we also substitute away the occurences
of $(HOST_DIR) in the calculation of the compiler hash. This is done
regardless of the setting of BR2_CCACHE_USE_BASEDIR because it's
quite harmless.
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Since we always have a toolchain wrapper now, we can move the ccache
call to the toolchain wrapper.
The hostcc ccache handling obviously stays.
The global addition of ccache to TARGET_CC/CXX is removed, but many
individual packages and infras still add it. This means we have a
chain like this: ccache -> toolchain-wrapper -> ccache -> gcc
However, this is fairly harmless: for cache misses, the inner ccache
just adds overhead and for cache hits, the inner ccache is never
called. Later patches will remove these redundant ccache calls.
As a side effect, perl now supports ccache as well.
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Cc: Danomi Manchego <danomimanchego123@gmail.com>
Cc: Károly Kasza <kaszak@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
The toolchain wrapper will be reused for the internal toolchain, so it
belongs in the toolchain directory. Also, the ext- prefix is removed
from it. The build commands are moved to a new toolchain-wrapper.mk.
The wrapper arguments that are also relevant for the internal toolchain
wrapper are moved to toolchain-wrapper.mk, the rest stays in
toolchain-external.mk.
While we're at it, move the building of the toolchain wrapper to the
build step of toolchain-external. There is no specific reason to do
this, other than that it fits better semantically. Also remove the
MESSAGE call, otherwise we'd see:
>>> toolchain-external undefined Building
>>> toolchain-external undefined Building toolchain wrapper
/usr/bin/gcc ...
Having an extra "Building toolchain wrapper' message is pointless.
The useless condition on $(BR2_TARGET_OPTIMIZATION) is removed. It was
always true because it wasn't qstrip'ped first, so clearly it works
without that condition as well.
Also rewrapped some comments and removed the 'external' reference.
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Cc: Fabio Porcedda <fabio.porcedda@gmail.com>
Cc: Jérôme Oufella <jerome.oufella@savoirfairelinux.com>
Reviewed-by: Romain Naour <romain.naour@openwide.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
