has support for the .codeXX directives). However, it is desirable, for
a time, to allow kernels to be built with clang 3.4. Historically, it
has been advantageous to allow stable X-1 to build kernels the old
way (so long as the impact of doing so is small), and this restores
that ability.
Also, centralize the addition of ${ASM_CFLAGS.${.IMPSRC}}, place it in
kern.mk rather than kern.pre.mk so that all modules can benefit, and
give the same treatment to CFLAGS in kern.mk as well.
building with gcc 4.2
This has been requested several times over the past few months by several
people (including me), because gcc 4.2 just gets it wrong too often. It's
causing us to litter the code with lots of bogus initializers just to
squelch the warnings. We still have clang and coverity telling us about
uninitialized variables, and they do so more accurately.
CWARNFALGS.$file centrally so we don't have to have it in all the
places. Remove a few warning flags that are no longer needed.
Also, always use -Wno-unknown-pragma to (hopefully temporarily) work
around #pragma ident in debug.h in the opensolaris code. Remove some
stale warning suppression that's no longer necessary.
the place where the C dialect is selected. Have a fairly long list
of newly requires warning suppression for clang 3.5.0, also
centralized in kern.mk. Survive the fallout of the removal of
bsd.sys.mk from bsd.kmod.mk.
raft of new warnings that appear to be on by default in clang 3.5.0.
Fix RPI-B build issues with new clang not liking the ability to pass
arbitrary flags to as, since some flags are more arbitrary (and thus
verboten) than others.
These warnings should be actually fixed in the code, but this is a
band-aide to get things (almost) building again.
cutover is, but we need better tools to cope with inline tuning per
compiler version than we have. This is a quick bandaid until such
tools are around.
completely silenced. Make sure these warnings appear again, so there is
some incentive to fix them, but do not error out the whole kernel build
for them.
Noticed by: steven@pyro.eu.org
PR: 191867
MFC after: 3 days
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
o KMODDEPS warning is 15 years stale. Remove it.
o MK_CTF will always be defined now, so no need to test to see if it
is defined.
o no need to define MK_FORMAT_EXTENTIONS if undefined anymore.
generate dwarf4 by default as well, so always force dwarf2 when
generating debugging data. It is harmless on older versions of both
clang and gcc, but required on newer ones.
though it works w/o it for some reason, contrary to our reading of
make(1)). Also add a comment explaining things a bit better so there's
one less mystery that must be answered with svn blame.
Submitted by: ian@
add it in kern.mk, but only if we're using clang. While this
option is supported by both clang and gcc, in the future there
may be changes to clang which change the defaults that require
a tweak to build our kernel such that other tools in our tree
will work. Set a good example by forcing -gdwarf-2 only for
clang builds, and only if the user hasn't specified another
dwarf level already. Update UPDATING to reflect the changed
state of affairs. This also keeps us from having to update
all the ARM kernels to add this, and also keeps us from
in the future having to update all the MIPS kernels and is
one less place the user will have to know to do something
special for clang and one less thing developers will need
to do when moving an architecture to clang.
Reviewed by: ian@
MFC after: 1 week
-mcmodel=large, for now. While here, disable -msoft-float for clang
since it is not supported, and add -fno-dwarf2-cfi-asm to stop it from
emitting .cfi directives, which GNU as does not support.
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.
The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3. The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.
Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>
MFC after: 1 month
for signed values due to a compiler authors considering integer
overflow as impossible.
The change follows suit of other projects taking the same measure.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
type of compiler is being used (currently clang or gcc). COMPILER_TYPE
is set in the new bsd.compiler.mk file based on the value of the CC
variable or, should it prove informative, by running ${CC} --version
and examining the output.
To avoid negative performance impacts in the default case and correct
value for COMPILER_TYPE type is determined and passed in the environment
of submake instances while building world.
Replace adhoc attempts at determining the compiler type by examining
CC or MK_CLANG_IS_CC with checks of COMPILER_TYPE. This eliminates
bootstrapping complications when first setting WITH_CLANG_IS_CC.
Sponsored by: DARPA, AFRL
Reviewed by: Yamaya Takashi <yamayan@kbh.biglobe.ne.jp>, imp, linimon
(with some modifications post review)
MFC after: 2 weeks
sys/dev/mps/mps_sas.c:861:1: error: function 'mpssas_discovery_timeout' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
mpssas_discovery_timeout(void *data)
^
Because the driver is obtained from upstream, we don't want to modify
it; just silence the warning instead, it is harmless.
MFC after: 3 days
to match reality: clang does _not_ disable SSE automatically when
-mno-mmx is used, you have to specify -mno-sse explicitly.
Note this was the case even before r232894, which only makes a change in
the 'positive' flag case; e.g. when you specify -msse, MMX gets enabled
too.
MFC after: 1 week
of the Cavium Simple Executive, which violates large function growth rules
in such a way that simply increasing the large function growth parameter is
insufficient.
that it is better to error out when people attempt to build using the
wrong bsd.*.mk files, than to silently ignore the problem.
This means, that after this commit, if you want to build kernel modules
by hand (or via a port) from a head source tree, you *must* make sure
the files in /usr/share/mk are in sync with that tree. If that isn't
possible, for example when you are running on an older FreeBSD branch,
you can:
- Run "make buildenv" from your head source tree, to have the correct
environment setup. (It's advisable to have run "make buildworld", or
at a minimum "make toolchain" first.)
- Alternatively, set MAKESYSPATH to the share/mk directory under your
head source tree. If your build tools are too old, other problems may
still occur.
- Alternatively, use "make -m" and specify the share/mk directory under
your head source tree. Again, build tools that are too old may still
result in trouble.
MFC after: 2 weeks
kernel modules using their old installed /usr/share/mk/bsd.*.mk files,
instead of the updated ones in their source tree. This leads to errors
like:
"sys/conf/kmod.mk", line 111: Malformed conditional (${MK_CLANG_IS_CC} == "no" && ${CC:T:Mclang} != "clang")
Obviously, these errors will go away after a "make installworld", or
alternatively, by using "make buildenv" before attempting to manually
build modules.
However, since it is apparently an expected use case to build using old
.mk files, change the way we test for clang, so it also works when the
MK_CLANG_IS_CC macro doesn't exist.
Note the conditional expressions are becoming rather unreadable now, but
I will attempt to fix that on a followup commit.
MFC after: 2 weeks
installs clang as /usr/bin/cc, /usr/bin/c++ and /usr/bin/cpp.
Note this does *not* disable building and installing gcc, which will
still be available as /usr/bin/gcc, /usr/bin/g++ and /usr/bin/gcpp. If
you want to disable gcc completely, you must use WITHOUT_GCC.
MFC after: 2 weeks
sys/dev/hpt27xx/osm_bsd.c, since it gets the following warnings:
sys/dev/hpt27xx/osm_bsd.c:1180:25: error: format string is not a string literal (potentially insecure) [-Werror,-Wformat-security]
S_IRUSR | S_IWUSR, driver_name);
^~~~~~~~~~~
@/dev/hpt27xx/hpt27xx_config.h:46:21: note: expanded from:
#define driver_name hpt27xx_driver_name
^~~~~~~~~~~~~~~~~~~
Since 'hpt27xx_driver_name' is a constant string symbol (coming from the
proprietary hpt27xx_lib.o file), there is no security problem.
Because this driver is provided by the vendor, and applying changes
requires re-certification and other bureaucratic exercises, just disable
the warning for now.
MFC after: 1 week
several sys/cam/ctl files, since these get the following warnings:
In file included from sys/cam/ctl/ctl_backend.c:60:
sys/cam/ctl/ctl_private.h:300:30: error: variable 'page_index_template' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static struct ctl_page_index page_index_template[] = {
^
These warnings are tricky to fix without a lot of overhaul, and they are
harmless, so disable them for now.
MFC after: 1 week
All of these are harmless, and are in fact used to shut up warnings from
lint.
While here, remove -Wno-missing-prototypes from the xfs module
Makefile, as I could not reproduce those warnings either with gcc or
clang.
MFC after: 1 week
with clang. There are several macros in these files that return values,
and in some cases nothing is done with them, but it is completely
harmless. For some other files, also disable -Wconstant-conversion,
since that triggers a false positive with the DMA_BIT_MASK() macro.
MFC after: 1 week
kernel builds. All the instances of this warning in our tree are
completely harmless, and many people seem to like adding extra
parentheses to make precedence clearer.
MFC after: 1 week
builds. All the instances of this warning in our tree are completely
harmless. (Most of the empty bodies look to be used simply as reminder
for the developer to add something later.)
While here, assign to CWARNEXTRA with ?=, so it can be overridden
easily, if needed.
MFC after: 1 week
CWARNEXTRA variable, which gets included into the initial CWARNFLAGS
setting. This makes it easier to override CWARNFLAGS with completely
custom settings (including enabling any disabled warnings).
Reminded by: arundel
MFC after: 1 week
might be useful in some cases, but which are not severe enough to error
out the whole kernel build. Display them anyway, so there is at least
some incentive to fix them eventually.
Start with -Wtautological-compare warnings. These usually occur when
people check if unsigned quantities are negative, or similar cases. To
clean these up would be painful, and might give problems if the base
type which is compared against changes to signed later on.
MFC after: 1 week
as it gets the following warning:
sys/dev/asr/asr.c:1836:29: warning: array index of '58' indexes past the end of an array (that contains 1 element) [-Warray-bounds]
while ((len > 0) && (sg < &((PPRIVATE_SCSI_SCB_EXECUTE_MESSAGE)
^
sys/dev/asr/i2omsg.h:934:8: note: array 'Simple' declared here
I2O_SGE_SIMPLE_ELEMENT Simple[1];
^
This is a false positive, since I2O_SG_ELEMENT::Simple is not declared
as a C99 flexible array member, but in the old (but more portable) way.
At run-time, the proper number of array elements will hopefully have
been allocated.
MFC after: 1 week
there are some places in the kernel where fixing them is too disruptive,
or where there is a false positive.
In this case, disable -Wconstant-conversion for two aic7xxx-related
files, as they get the following warning on i386 (and possibly on other
32-bit arches):
sys/dev/aic7xxx/ahc_pci.c:112:10: warning: implicit conversion from 'long long' to 'bus_addr_t' (aka 'unsigned int') changes value from 549755813887 to 4294967295 [-Wconstant-conversion]
? 0x7FFFFFFFFFLL
~~^~~~~~~~~~~~~~
This is a false positive, since the code only passes the 0x7FFFFFFFFFLL
argument, if sizeof(bus_addr_t) is larger than 4 (e.g. on 64 bit arches,
or when PAE is enabled on i386). The code could be refactored to do
compile-time checks, but that is more disruptive.
MFC after: 1 week
- CTFCONVERT_CMD=... is a hack (should be defined to empty string instead):
make(1) should be taught to ignore empty commands silently in compat mode
(as it does in !compat mode, GNU make also silently ignores empty commands)
and to skip printing empty commands in !compat mode
- config(8) should generate ${NORMAL_CTFCONVERT} invocation without '@':
this will allow to simplify kern.pre.mk even more and lessen the number
of shell invocations during kernel build when CTF is turned off
- WITH_CTF can now be converted to usual MK_CTF=yes/no infrastructure
Pointy hat to: fjoe [1]
Alexander Best (arundel@).
For clang, -fdiagnostics-show-option is enabled by default, but for gcc it
isn't. This option will report which -W* flag was responsible for triggering
a certain warning. This will bring gcc warnings closer to the ones clang emits
and might also help developers track down tinderbox failures a bit quicker.
Submitted by: arundel
flags are also specified. This change makes use of this behaviour and removes
unneeded -mno-* flags.
Note that clang does not yet enable AVX support for any CPU. However at some
point in the future it will and since we definitely want to disable it for the
kernel, we might as well add the -mno-avx flag now.
Submitted by: arundel
developers committing new code with broken include directories.
Fix a few whitespace issues.
Improve a couple of comments.
-W is now deprecated and is referred to as -Wextra (see gcc(1)).
Submitted by: arundel
This support has not worked for several years, and is not likely to work
again, unless Intel decides to release a native FreeBSD version of their
compiler. ;)
Makefiles or *.mk files, use ${CC:T:Mfoo} instead, so only the basename
of the compiler command (excluding any arguments) is considered.
This allows you to use, for example, CC="/nondefault/path/clang -xxx",
and still have the various tests in bsd.*.mk identify your compiler as
clang correctly.
ICC if cases were also changed.
Submitted by: Dimitry Andric <dimitry at andric.com>
are some problems with static executables), make.conf (would also
affect ports which do not use GNU make and do not override the
compile targets) or in the kernel config (via "makeoptions
WITH_CTF=yes").
Additional (related) changes:
- propagate WITH_CTF to module builds
- do not add -g to the linker flags, it's a noop there anyway
(at least according to the man page of ld)
- do not add -g to CFLAGS unconditionally
we need to have a look if it is really needed (IMO not) or if there
is a way to add it only when WITH_CTF is used
Note: ctfconvert / ctfmerge lines will not appear in the build output,
to protect the innocent (those which do not build with WITH_CTF would
see the shell-test and may think WITH_CTF is used).
Reviewed by: imp, jhb, scottl (earlier version)
Discussed on: arch@
r201902 | imp | 2010-01-09 10:16:19 -0700 (Sat, 09 Jan 2010) | 2 lines
Fix comment, which was missed in an earlier commit...
r195669 | gonzo | 2009-07-13 17:03:44 -0600 (Mon, 13 Jul 2009) | 3 lines
- Remove -mno-dsp from CFLAGS. MIPS DSP ASE is off by default
now (as it should be)
- It is opt-out for now so as to give it maximum testing, but it may be
turned opt-in for stable branches depending on the consensus. You
can turn it off with WITHOUT_SSP.
- WITHOUT_SSP was previously used to disable the build of GNU libssp.
It is harmless to steal the knob as SSP symbols have been provided
by libc for a long time, GNU libssp should not have been much used.
- SSP is disabled in a few corners such as system bootstrap programs
(sys/boot), process bootstrap code (rtld, csu) and SSP symbols themselves.
- It should be safe to use -fstack-protector-all to build world, however
libc will be automatically downgraded to -fstack-protector because it
breaks rtld otherwise.
- This option is unavailable on ia64.
Enable GCC stack protection (aka Propolice) for kernel:
- It is opt-out for now so as to give it maximum testing.
- Do not compile your kernel with -fstack-protector-all, it won't work.
Submitted by: Jeremie Le Hen <jeremie@le-hen.org>
compiler invocation. This is just to help get over the hump of people
tracking down bugs that may cross the GCC 4.2 upgrade.
It is envisioned that this option goes away after a suitable amount
of time.
Switch ia64 kernels to -fpic. This is likely wrong, but at least gets
ia64 kernels to compile and link with GCC 4.2. The previous -mno-sdata
trick is not working anymore.
`-Wundef'
Warn whenever an identifier which is not a macro is encountered in
an `#if' directive, outside of `defined'. Such identifiers are
replaced with zero.
I think all we really need is -fno-sse2.
I really don't like cluttering up the compiler invocation,
but this bigger hammer will fix reported problems for now.
Intel C/C++ compiler (lang/icc) to build the kernel.
The icc CPUTYPE CFLAGS use icc v7 syntax, icc v8 moans about them, but
doesn't abort. They also produce CPU specific code (new instructions
of the CPU, not only CPU specific scheduling), so if you get coredumps
with signal 4 (SIGILL, illegal instruction) you've used the wrong
CPUTYPE.
Incarnations of this patch survive gcc compiles and my make universe.
I use it on my desktop.
To use it update share/mk, add
/usr/local/intel/compiler70/ia32/bin (icc v7, works)
or
/usr/local/intel_cc_80/bin (icc v8, doesn't work)
to your PATH, make sure you have a new kernel compile directory
(e.g. MYKERNEL_icc) and run
CFLAGS="-O2 -ip" CC=icc make depend
CFLAGS="-O2 -ip" CC=icc make
in it.
Don't compile with -ipo, the build infrastructure uses ld directly to
link the kernel and the modules, but -ipo needs the link step to be
performed with Intel's linker.
Problems with icc v8:
- panic: npx0 cannot be emulated on an SMP system
- UP: first start of /bin/sh results in a FP exception
Parts of this commit contains suggestions or submissions from
Marius Strobl <marius@alchemy.franken.de>.
Reviewed by: silence on -arch
Submitted by: netchild
the amd64 implementation of the pcpu macros is even more verbose than on
i386 and that causes gcc to way overestimate the complexity of this
2-instruction macro. The other platforms can probably lower their
default values.
section to stop gcc generating the dwarf2 .eh_frame unwind tables. It
is dead weight for the time being. Maybe it can be used to perform
stack traces and/or get the location of function arguments in ddb, but
that requires a dwarf2 runtime interpreter, which we do not have.
Approved by: re (amd64 "safe" bits)
systems. Of note:
- Implement a direct mapped region using 2MB pages. This eliminates the
need for temporary mappings when getting ptes. This supports up to
512GB of physical memory for now. This should be enough for a while.
- Implement a 4-tier page table system. Most of the infrastructure is
there for 128TB of userland virtual address space, but only 512GB is
presently enabled due to a mystery bug somewhere. The design of this
was heavily inspired by the alpha pmap.c.
- The kernel is moved into the negative address space(!).
- The kernel has 2GB of KVM available.
- Provide a uma memory allocator to use the direct map region to take
advantage of the 2MB TLBs.
- Fixed some assumptions in the bus_space macros about the ability
to fit virtual addresses in an 'int'.
Notable missing things:
- pmap_growkernel() should be able to grow to 512GB of KVM by expanding
downwards below kernbase. The kernel must be at the top 2GB of the
negative address space because of gcc code generation strategies.
- need to fix the >512GB user vm code.
Approved by: re (blanket)
Fix the "@gprel relocation against dynamic symbol xxx" linker error.
Variables defined in the link unit and small enough to be put in the
short data section will have a gp-relative access sequence (using the
@gprel relocation). It is invalid to have @gprel relocations in shared
libraries, because they are to be resolved by the static linker and
not the dynamic linker. The -fpic option will cause @ltoff relocations
for @gprel relocations, but the side-effects are untested (if any).
Instead, disable/eliminate the short data section to achieve the same.
This reduces the size of GENERIC's text space by 73999 bytes (about 2%).
The bloat is from approximately 3437 strings longer than 31 characters
being padded to a 32-byte boundary.
ev6 or pca56 etc this downgrades the cpu specification passed to gas.
As a result, gas will fail when gcc generates media instructions (in
uipc_usrreq.c). This only affects what gas will accept, not what gcc
generates or what our *.s file contain.
back to -fformat-extensions (or whatever) when we have the functionality.
We are gaining warnings again that should be fixed but the are being hidden
by NO_WERROR and all the -Wformat noise.
is not implied by -Wall as claimed by gcc.1. Adding it causes a
measly 7193 new warnings for LINT, mostly for "unused parameter" and
"comparison between signed and unsigned".
variables were lost when we removed -W, and 23 new ones including at
least one serious one have crept in for LINT.
Restored -Winline to CFLAGS. This gives only 3 old warnings and 1 new
for LINT.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
2.2 are more obvious. -Winline is unimportant, but -W gives thousands
of warnings for comparisions. Turning off -W also loses warnings for:
- auto variables clobbered by longjmp. Not much of a problem in the kernel.
- functions returning without a value. I don't like losing this.
- an expression statement or the left side of a comma operand contains no
side effects. Turning this off also stops warnings for the low quality
debugging macros in gsc.c and lpt.c.
Should be in 2.2.
Also disabled -Wunused. It caused too many warnings even for me.
The sign mismatch warnings should be fixed first. They are more
important and harder to disable (they are controlled by -W, which
controls too many things).
