Use -Wno-unused-but-set-variable for kernel builds with clang13.
To turn this warning back on, set the following in src.conf:
WITH_SET_BUT_NOTUSED_KERNEL_WARNINGS=
Reviewed by: mjg, imp
Differential Revision: https://reviews.freebsd.org/D34784
Define NO_WUNUSED_BUT_SET_VARIABLE for newer clang, and use it in ATH_C
to account for different clang versions. Use it in Makefiles as well.
Sponsored by: Netflix
Reviewed by: kevans, jhb
Differential Revision: https://reviews.freebsd.org/D34408
GCC is more pedantic than clang about warning when a function doesn't
handle undefined enum values (see GCC bug 87950). Clang's warning
gives a more pragmatic coverage and should find any real bugs, so
disable the warning for GCC rather than adding __unreachable
annotations to appease GCC.
Reviewed by: imp, emaste
Differential Revision: https://reviews.freebsd.org/D34147
Parts of zstd, used in openzfs and other places, trigger a new clang 14
-Werror warning:
```
sys/contrib/zstd/lib/decompress/huf_decompress.c:889:25: error: use of bitwise '&' with boolean operands [-Werror,-Wbitwise-instead-of-logical]
(BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
While the warning is benign, it should ideally be fixed upstream and
then vendor-imported, but for now silence it selectively.
MFC after: 3 days
clang doesn't implement it, and Linux doesn't enforce it. As a
result, new instances keep cropping up both in FreeBSD's code and in
upstream sources from vendors.
Reviewed by: emaste
Differential Revision: https://reviews.freebsd.org/D34144
Remove sys/mips as the next step of decomissioning mips from the tree.
Remove mips special cases from the kernel make files. Remove the mips
specific linker scripts.
Sponsored by: Netflix
GCC complains about the use of alloca() with variable sizes (for XSAVE
state len) in sendsig() for i386. Modern XSAVE state is probably
getting a bit large for the i386 kstack, but downgrade the error to a
warning.
Reviewed by: kib, emaste
Differential Revision: https://reviews.freebsd.org/D31934
Clang 13.0.0 now has a -Wunused-but-set-variable warning similar to the
one gcc has had for quite a while. Since this triggers *very* often for
our kernel builds, don't make it a hard error, but leave the warning
visible so is some incentive to fix the instances.
MFC after: 3 days
With current generation clang/llvm it can pass all of our tests in
libc/ssp.
While here, remove the extra MACHINE_CPUARCH check for mips. SSP is
included in BROKEN_OPTIONS for this architecture in src.opts.mk, which
is enough to ensure normal builds won't set SSP_CFLAGS.
Reviewed by: kevans, imp, emaste
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D31400
This warning is very rarely useful (inline is a hint and not mandatory).
This flag results in many warnings being printed when compiling C++
code that uses the standard library with GCC.
This flag was originally added in back in r94332 but the flag is a no-op
in Clang ("This diagnostic flag exists for GCC compatibility, and has no
effect in Clang"). Removing it should make the GCC build output slightly
more readable.
Reviewed By: jrtc27, imp
Differential Revision: https://reviews.freebsd.org/D29235
Clang 12 no longer supports -Wno-error-..., only the -Wno-error=...
style (which is already used everywhere else in the tree).
Differential Revision: https://reviews.freebsd.org/D29157
When I synchronized kern.mk with bsd.sys.mk, I accidentally changed
CCLDFLAGS to LDFLAGS which is not used by the kernel builds. This commit
should unbreak the GitHub actions cross-build CI. I didn't notice it
locally because cheribuild already passes -fuse-ld in the linker flags as
it predates this being done in the makefiles.
Reported By: Jose Luis Duran
Fixes: 172a624f0 ("Silence annoying and incorrect non-default linker warning with GCC")
The CROSS_TOOLCHAIN GCC .mk files include -B${CROSS_BINUTILS_PREFIX}, so
GCC will select the right linker and we don't need to warn.
While here also apply 17b8b8fb5f to kern.mk.
Test Plan: no more warning printed with CROSS_TOOLCHAIN=mips-gcc6
Reviewed By: jhb
Differential Revision: https://reviews.freebsd.org/D29015
After the removal of obsolete GDB 6.1.1 from the base system in
1c0ea326aa we no longer need to downgrade to DWARF2 debug info.
We will need to ensure that our tools (e.g. ctfconvert) handle DWARF5
prior to it becoming the default in the Clang and GCC versions we use.
Reported by: jhb
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
-mno-align-long-strings was a flag maintained by FreeBSD for the
now-deleted in-tree gcc. Upstream gcc has no such flag, so just drop
it.
The flag was originally submitted by bde and committed in 2002 (svn
r97911 & r104455). However, upstream gcc did address this same issue in
2004 (gcc svn r76694 / git 4137ba7ab7a), reducing long string alignment
in general, and to 1 with -Os.
Reviewed by: kib
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D27768
These options need to be in the kern.opts.mk file to be alive for kernel
and module builds. This also reverts r367579 since that's not needed with
this fix: the host's bsd.opts.mk is irrelevant.
Reviewed by: brooks@
Differential Revision: https://reviews.freebsd.org/D27170
When building out-of-tree modules, it appears that the system share/mk
is used, but sys/conf/kern.mk is used. That results in MK_INIT_ALL_ZERO
being undefined. In the interest of maximum compatability, check
that MK_INIT_ALL_* and COMPILER_FEATURES are defined before comparing
their values.
Reported by: mmacy
Sponsored by: DARPA
There are two options:
- WITH_INIT_ALL_ZERO: Zero all variables on the stack.
- WITH_INIT_ALL_PATTERN: Initialize variables with well-defined patterns.
The exact pattern are a compiler implementation detail and vary by type.
They are somewhat documented in the LLVM commit message:
https://reviews.llvm.org/rL349442
I've used WITH_INIT_ALL_* to match Microsoft's InitAll feature rather
than naming them after the LLVM specific compiler flags.
In a range of consumer products, options like these are used in
both debug and production builds with debugs builds using patterns
(intended to provoke crashes on use of uninitialized values) and
production using zeros (deemed more likely to lead to harmless
misbehavior or NULL-pointer dereferences).
Reviewed by: emaste
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27131
This is the initial set up for PowerPC64LE.
The current plan is for this arch to remain experimental for FreeBSD 13.
This started as a weekend learning project for me and kinda snowballed from
there.
(More to follow momentarily.)
Reviewed by: imp (earlier version), emaste
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D26399
When using relative paths for the linker we have to transform the name
since clang does not like -fuse-ld=ld.lld and instead requires -fuse-ld=lld
(the same also applies for ld.bfd).
This is needed so that setting LD/XLD is not ignored when linking with $CC
instead of directly using $LD. Currently only clang accepts an absolute
path for -fuse-ld= (Clang 12+ will add a new --ld-path flag), so we now
warn when building with GCC and $LD != "ld" since that might result in the
wrong linker being used.
We have been setting XLD=/path/to/cheri/ld.lld in CheriBSD for a long time and
used a similar version of this patch to avoid linking with /usr/bin/ld.
This change is also required when building FreeBSD on an Ubuntu with Clang:
In that case we set XCC=/usr/lib/llvm-10/bin/clang and since
/usr/lib/llvm-10/bin/ does not contain a "ld" binary the build fails with
`clang: error: unable to execute command: Executable "ld" doesn't exist!`
unless we pass -fuse-ld=/usr/lib/llvm-10/bin/ld.lld.
This change passes -fuse-ld instead of copying ${XLD} to WOLRDTMP/bin/ld
since then we would have to ensure that this file does not exist while
building the bootstrap tools. The cross-linker might not be compatible with
the host linker (e.g. when building on macos: host-linker= Mach-O /usr/bin/ld,
cross-linker=LLVM ld.lld).
Reviewed By: brooks, emaste
Differential Revision: https://reviews.freebsd.org/D26055
Assume gcc is at least 6.4, the oldest xtoolchain in the ports tree.
Assume clang is at least 6, which was in 11.2-RELEASE. Drop conditions
for older compilers.
Reviewed by: imp (earlier version), emaste, jhb
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D24802
Now that hw.machine_arch handles soft-float vs hard-float there is no
longer a reason for this config.
Submitted by: mhorne (kern.mk hunk)
Reviewed by: imp (earlier version), kp
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24544
Use __riscv_flen instead of __riscv_float_abi_soft. While the latter works for
userland (and one could argue it's more correct), it fails for the kernel. We
compile the kernel with -mabi=lp64 (eg soft float abi) to avoid floating point
instructions in the kernel. We also compile the kernel -march=rv64imafdc for
hard float kernels (eg those with options FPE), but with -march=rv64imac for
softfloat kernels (eg those with FPE). Since we do this, in the kernel (as in
userland) __riscv_flen will be defined for 'riscv64' and not for 'riscv64sf'.
This also removes the -DMACHINE_ARCH hack now that it's no longer needed.
Longer term, we should return the ABI from the sysctl hw.machine_arch like on
amd64 for i386 binaries.
Suggested by: mhorne@
Differential Revision: https://reviews.freebsd.org/D23813
GENERICSF is just like GENERIC, only creates a soft-float kernel. Omit it from the
universe build for now.
Reviewed by: philip
Differential Revision: https://reviews.freebsd.org/D23812
the ! operator should have been a ~ instead:
Merge r357348 from the clang 10.0.0 import branch:
Disable new clang 10.0.0 warnings about converting the result of
shift operations to a boolean in tpm(4):
sys/dev/tpm/tpm_crb.c:301:32: error: converting the result of '<<' to a boolean; did you mean '(1 << (0)) != 0'? [-Werror,-Wint-in-bool-context]
WR4(sc, TPM_CRB_CTRL_CANCEL, !TPM_CRB_CTRL_CANCEL_CMD);
^
sys/dev/tpm/tpm_crb.c:73:34: note: expanded from macro 'TPM_CRB_CTRL_CANCEL_CMD'
#define TPM_CRB_CTRL_CANCEL_CMD BIT(0)
^
sys/dev/tpm/tpm20.h:60:19: note: expanded from macro 'BIT'
#define BIT(x) (1 << (x))
^
Such warnings can be useful in C++ contexts, but not so much in kernel
drivers, where this type of bit twiddling is commonplace. So disable
it for this case.
Noticed by: cem
MFC after: 3 days
operations to a boolean in tpm(4):
sys/dev/tpm/tpm_crb.c:301:32: error: converting the result of '<<' to a boolean; did you mean '(1 << (0)) != 0'? [-Werror,-Wint-in-bool-context]
WR4(sc, TPM_CRB_CTRL_CANCEL, !TPM_CRB_CTRL_CANCEL_CMD);
^
sys/dev/tpm/tpm_crb.c:73:34: note: expanded from macro 'TPM_CRB_CTRL_CANCEL_CMD'
#define TPM_CRB_CTRL_CANCEL_CMD BIT(0)
^
sys/dev/tpm/tpm20.h:60:19: note: expanded from macro 'BIT'
#define BIT(x) (1 << (x))
^
Such warnings can be useful in C++ contexts, but not so much in kernel
drivers, where this type of bit twiddling is commonplace. So disable it
for this case.
MFC after: 3 days
This is lame, but it's what we already do for the clang build. We take
misaligned pointers into network header structures in many places.
Reviewed by: ian
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22876
When the linker doesn't have this feature, add -mno-relax to CFLAGS
on RISC-V.
Define the feature for ld.bfd, but not lld. If lld gains relaxation
support in a newer version, we can enable it for those versions of lld
in bsd.linker.mk.
Reviewed by: mhorne
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D22659
Use the -march and -mabi flags for both gcc and clang as they are
compatible. Specify the "medium" code model separately as it goes by the
name "medany" under gcc, although they are equivalent.
Reviewed by: markj
Approved by: markj (mentor)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D21436
It is part of -Wformat, which is enabled by -Wall. Empty format strings are
well defined and it is perfectly reasonable to expect them in a formatting
interface.
Unmapped mbufs allow sendfile to carry multiple pages of data in a
single mbuf, without mapping those pages. It is a requirement for
Netflix's in-kernel TLS, and provides a 5-10% CPU savings on heavy web
serving workloads when used by sendfile, due to effectively
compressing socket buffers by an order of magnitude, and hence
reducing cache misses.
For this new external mbuf buffer type (EXT_PGS), the ext_buf pointer
now points to a struct mbuf_ext_pgs structure instead of a data
buffer. This structure contains an array of physical addresses (this
reduces cache misses compared to an earlier version that stored an
array of vm_page_t pointers). It also stores additional fields needed
for in-kernel TLS such as the TLS header and trailer data that are
currently unused. To more easily detect these mbufs, the M_NOMAP flag
is set in m_flags in addition to M_EXT.
Various functions like m_copydata() have been updated to safely access
packet contents (using uiomove_fromphys()), to make things like BPF
safe.
NIC drivers advertise support for unmapped mbufs on transmit via a new
IFCAP_NOMAP capability. This capability can be toggled via the new
'nomap' and '-nomap' ifconfig(8) commands. For NIC drivers that only
transmit packet contents via DMA and use bus_dma, adding the
capability to if_capabilities and if_capenable should be all that is
required.
If a NIC does not support unmapped mbufs, they are converted to a
chain of mapped mbufs (using sf_bufs to provide the mapping) in
ip_output or ip6_output. If an unmapped mbuf requires software
checksums, it is also converted to a chain of mapped mbufs before
computing the checksum.
Submitted by: gallatin (earlier version)
Reviewed by: gallatin, hselasky, rrs
Discussed with: ae, kp (firewalls)
Relnotes: yes
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20616
-Wformat-zero-length does not highlight any particularly wrong code and it
is especially meaningless for device_printf(). Turn it off entirely to
remove a source of false positives.
Sponsored by: Dell EMC Isilon
add gcov support and export results as files in debugfs
Reviewed by: hps@
MFC after: 1 week
Sponsored by: iX Systems
Differential Revision: https://reviews.freebsd.org/D19260
This fixes a warning seen when compiling amd64 GENERIC with clang 7.
Also remove the workaround added in r337324. clang 7 and gcc 4.2
generate the same code with or without the code change.
Reviewed by: imp (previous version)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D18603
CLANG_NO_IAS34 was introduced in r276696 to allow then-HEAD kernels to
be built with clang 3.4 in FreeBSD 10. As FreeBSD 11 and later includes
a version of Clang with a sufficiently capable integrated assembler we
do not need the workaround any longer.
Sponsored by: The FreeBSD Foundation
This was disabled recently due to lack of support in KDB disassembler
and DTrace FBT provider. Support for 'C'-extension to both of these was
added, so we can now enable 'C'-extension.
This reduces size of the kernel important for low-end embedded devices,
and saves cache footprint for high perfomance machines.
Approved by: re (kib)
Sponsored by: DARPA, AFRL
It works excellent, but KDB disassembler and DTrace FBT provider for
RISC-V do lack support for it. They currently handle 4-byte instructions
only, while C-compressed ISA extension introduces 2-byte instructions
freely mixing them together.
So disable it for now.
Reviewed by: markj@
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16436
Remove all the big-endian arm architectures (ixp425 and ixp435)
support in the kernel and associated drivers.
Differential Revision: https://reviews.freebsd.org/D16257
