On clang emits the compiler version string into debug information
by default for both dwarf and codeview. That makes compiler output
needlessly compiler-version-dependent which makes e.g. comparing
object file outputs during a bisect hard. So it's nice if there's
an easy way to turn this off.
(On ELF, this flag also controls the .comment section, but that
part is ELF-only. The debug-info bit isn't.)
Differential Revision: https://reviews.llvm.org/D97695
When targeting a MSVC triple, --dependant-libs with the name of the clang runtime library for profiling is added to the command line args. In it's current implementations clang_rt.profile-<ARCH> is chosen as the name. When building a distribution using LLVM_ENABLE_PER_TARGET_RUNTIME_DIR this fails, due to the runtime file names not having an architecture suffix in the filename.
This patch refactors getCompilerRT and getCompilerRTBasename to always consider per-target runtime directories. getCompilerRTBasename now simply returns the filename component of the path found by getCompilerRT
Differential Revision: https://reviews.llvm.org/D96638
clang-cl already defaults to C17 for .c files, but no harm
in accepting these flags. Fixes PR48185.
Differential Revision: https://reviews.llvm.org/D95575
llvmArchToWindowsSDKArch() returns "" for non-intel non-arm archs.
We're checking for "/fake/lib/" which is followed by the result
of that function -- but if that returns an empty string, then that
trailing slash isn't there. As fix, just explicitly pass a triple
that's intel or arm (I randomly chose aarch64). Since the test runs
with -###, that arch doesn't have to be in LLVM_TARGETS_TO_BUILD.
These do for the Windows SDK path what D85998 did for
%VCToolsInstallDir% with /vctoolsdir: Offer a way to set them with an
explicit commandline switch.
With this (and /vctoolsdir), it's possible to compile and link
against hermetic vctools and winsdk directories with:
out/gn/bin/clang-cl win.c -fuse-ld=lld \
/vctoolsdir path/to/VC/Tools/MSVC/14.26.28801 \
/winsdkdir path/to/win_sdk
compared to a long list of -imsvc and /link /libpath: flags.
While here:
- Change the case of the "Include" folder inside the windows sdk
from "include" to "Include" to match on-disk case. Since the
Windows file system is case-insensitive this isn't a behavior
change, it's just a bit cleaner.
- Add libpath tests to the /vctoolsdir
- Add a FIXME about reading env vars for win sdk and ucrt sdk
if these flags aren't present, to match the VCToolsInstallDir
logic
We should also cache all these computed paths in the driver instead
of computing them every time they're queried, but that's for a future
patch.
It'd also be nice to invent a /winsysroot: flag that sets both
/vctoolsdir: and /winsdkdir: to some well-known subdirectory.
That's for a future patch as well.
Differential Revision: https://reviews.llvm.org/D95472
cl.exe doesn't understand Zd (in either MSVC 2017 or 2019), so neiter
should we. It used to do the same as `-gline-tables-only` which is
exposed as clang-cl flag as well, so if you want this behavior, use
`gline-tables-only`. That makes it clear that it's a clang-cl-only flag
that won't work with cl.exe.
Motivated by the discussion in D92958.
Differential Revision: https://reviews.llvm.org/D93458
Add an option to directly specify where the msvc toolchain lives for
clang-cl and avoid unwanted file and registry probes.
Differential revision: https://reviews.llvm.org/D85998
Some compiler-rt tests check for the presence of the compiler accepting
-fno-lto to add that flag. Otherwise some tests don't link due to
-flto mismatch between compiling and linking.
$ cmake ... -DLLVM_ENABLE_LTO=Thin ...
$ ninja projects/compiler-rt/lib/sanitizer_common/tests/Sanitizer-x86_64-Test.exe
previously failed, now links.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D85252
Summary:
-debug-info-kind=constructor reduces the amount of class debug info that
is emitted; this patch switches to using this as the default.
Constructor homing emits the complete type info for a class only when the
constructor is emitted, so it is expected that there will be some classes that
are not defined in the debug info anymore because they are never constructed,
and we shouldn't need debug info for these classes.
I compared the PDB files for clang, and there are 273 class types that are defined with `=limited`
but not with `=constructor` (out of ~60,000 total class types).
We've looked at a number of the types that are no longer defined with =constructor. The vast
majority of cases are something like class A is used as a parameter in a member function of
some other class B, which is emitted. But the function that uses class A is never called, and class A
is never constructed, and therefore isn't emitted in the debug info.
Bug: https://bugs.llvm.org/show_bug.cgi?id=46537
Subscribers: aprantl, cfe-commits, lldb-commits
Tags: #clang, #lldb
Differential Revision: https://reviews.llvm.org/D79147
Making -g[no-]column-info opt out reduces the length of a typical CC1 command line.
Additionally, in a non-debug compile, we won't see -dwarf-column-info.
Prior to this change, for a few compiler-rt libraries such as ubsan and
the profile library, Clang would embed "-defaultlib:path/to/rt-arch.lib"
into the .drective section of every object compiled with
-finstr-profile-generate or -fsanitize=ubsan as appropriate.
These paths assume that the link step will run from the same working
directory as the compile step. There is also evidence that sometimes the
paths become absolute, such as when clang is run from a different drive
letter from the current working directory. This is fragile, and I'd like
to get away from having paths embedded in the object if possible. Long
ago it was suggested that we use this for ASan, and apparently I felt
the same way back then:
https://reviews.llvm.org/D4428#56536
This is also consistent with how all other autolinking usage works for
PS4, Mac, and Windows: they all use basenames, not paths.
To keep things working for people using the standard GCC driver
workflow, the driver now adds the resource directory to the linker
library search path when it calls the linker. This is enough to make
check-ubsan pass, and seems like a generally good thing.
Users that invoke the linker directly (most clang-cl users) will have to
add clang's resource library directory to their linker search path in
their build system. I'm not sure where I can document this. Ideally I'd
also do it in the MSBuild files, but I can't figure out where they go.
I'd like to start with this for now.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D65543
This flag is like /showIncludes, but it only includes user headers and
omits system headers (similar to MD and MMD). The motivation is that
projects that already track system includes though other means can use
this flag to get consistent behavior on Windows and non-Windows, and it
saves tools that output /showIncludes output (e.g. ninja) some work.
implementation-wise, this makes `HeaderIncludesCallback` honor the
existing `IncludeSystemHeaders` bit, and changes the three clients of
`HeaderIncludesCallback` (`/showIncludes`, `-H`, `CC_PRINT_HEADERS=1`)
to pass `-sys-header-deps` to set that bit -- except for
`/showIncludes:user`, which doesn't pass it.
Differential Revision: https://reviews.llvm.org/D75093
All 130+ f_Group flags that take an argument allow it after a '=',
except for fdebug-complation-dir. Add a Joined<> alias so that
it behaves consistently with all the other f_Group flags.
(Keep the old Separate flag for backwards compat.)
This matches https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html
> -momit-leaf-frame-pointer
> -mno-omit-leaf-frame-pointer
>
> Omit or keep the frame pointer in leaf functions. The former behavior is the default.
-mno-omit-leaf-frame-pointer is currently a no-op because
TargetOptions::DisableFramePointerElim is only considered for non-leaf
functions.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D71167
Summary:
A new function pass (Transforms/CFGuard/CFGuard.cpp) inserts CFGuard checks on
indirect function calls, using either the check mechanism (X86, ARM, AArch64) or
or the dispatch mechanism (X86-64). The check mechanism requires a new calling
convention for the supported targets. The dispatch mechanism adds the target as
an operand bundle, which is processed by SelectionDAG. Another pass
(CodeGen/CFGuardLongjmp.cpp) identifies and emits valid longjmp targets, as
required by /guard:cf. This feature is enabled using the `cfguard` CC1 option.
Reviewers: thakis, rnk, theraven, pcc
Subscribers: ychen, hans, metalcanine, dmajor, tomrittervg, alex, mehdi_amini, mgorny, javed.absar, kristof.beyls, hiraditya, steven_wu, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D65761
These were added to the MS docs in
85b9b6967e
and are supposedly available in VS 2019 16.4 (though my 2019 Preview,
version 16.4.0-pre.1.0 don't seem to have them.)
llvm-svn: 373887
This broke compiling some ASan tests with never versions of MSVC/the Win
SDK, see https://crbug.com/996675
> MSVC 2017 update 3 (_MSC_VER 1911) enables /Zc:twoPhase by default, and
> so should clang-cl:
> https://docs.microsoft.com/en-us/cpp/build/reference/zc-twophase
>
> clang-cl takes the MSVC version it emulates from the -fmsc-version flag,
> or if that's not passed it tries to check what the installed version of
> MSVC is and uses that, and failing that it uses a default version that's
> currently 1911. So this changes the default if no -fmsc-version flag is
> passed and no installed MSVC is detected. (It also changes the default
> if -fmsc-version is passed or MSVC is detected, and either indicates
> _MSC_VER >= 1911.)
>
> As mentioned in the MSDN article, the Windows SDK header files in
> version 10.0.15063.0 (Creators Update or Redstone 2) and earlier
> versions do not work correctly with /Zc:twoPhase. If you need to use
> these old SDKs with a new clang-cl, explicitly pass /Zc:twoPhase- to get
> the old behavior.
>
> Fixes PR43032.
>
> Differential Revision: https://reviews.llvm.org/D66394
llvm-svn: 369647
MSVC 2017 update 3 (_MSC_VER 1911) enables /Zc:twoPhase by default, and
so should clang-cl:
https://docs.microsoft.com/en-us/cpp/build/reference/zc-twophase
clang-cl takes the MSVC version it emulates from the -fmsc-version flag,
or if that's not passed it tries to check what the installed version of
MSVC is and uses that, and failing that it uses a default version that's
currently 1911. So this changes the default if no -fmsc-version flag is
passed and no installed MSVC is detected. (It also changes the default
if -fmsc-version is passed or MSVC is detected, and either indicates
_MSC_VER >= 1911.)
As mentioned in the MSDN article, the Windows SDK header files in
version 10.0.15063.0 (Creators Update or Redstone 2) and earlier
versions do not work correctly with /Zc:twoPhase. If you need to use
these old SDKs with a new clang-cl, explicitly pass /Zc:twoPhase- to get
the old behavior.
Fixes PR43032.
Differential Revision: https://reviews.llvm.org/D66394
llvm-svn: 369402
with '-mframe-pointer'
After D56351 and D64294, frame pointer handling is migrated to tri-state
(all, non-leaf, none) in clang driver and on the function attribute.
This patch makes the frame pointer handling cc1 option tri-state.
Reviewers: chandlerc, rnk, t.p.northover, MaskRay
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D56353
llvm-svn: 366645
Use a tri-state enum to represent shouldUseFramePointer() and
shouldUseLeafFramePointer().
This simplifies the logic and fixes PR9825:
-fno-omit-frame-pointer doesn't imply -mno-omit-leaf-frame-pointer.
and PR24003:
/Oy- /O2 should not omit leaf frame pointer: this matches MSVC x86-32.
(/Oy- is a no-op on MSVC x86-64.)
and:
when CC1 option -mdisable-fp-elim if absent, -momit-leaf-frame-pointer
can also be omitted.
The new behavior matches GCC:
-fomit-frame-pointer wins over -mno-omit-leaf-frame-pointer
-fno-omit-frame-pointer loses out to -momit-leaf-frame-pointer
The behavior makes lots of sense. We have 4 states:
- 00) leaf retained, non-leaf retained
- 01) leaf retained, non-leaf omitted (this is invalid)
- 10) leaf omitted, non-leaf retained (what -momit-leaf-frame-pointer was designed for)
- 11) leaf omitted, non-leaf omitted
"omit" options taking precedence over "no-omit" options is the only way
to make 3 valid states representable with -f(no-)?omit-frame-pointer and
-m(no-)?omit-leaf-pointer.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D64294
llvm-svn: 365860
With this, `clang-cl /source-charset:utf-16 test.cc` now prints `invalid
value 'utf-16' in '/source-charset:utf-16'` instead of `invalid value
'utf-16' in '-finput-charset=utf-16'` before, and several other clang-cl
flags produce much less confusing output as well.
Fixes PR29106.
Since an arg and its alias can have different arg types (joined vs not)
and different values (because of AliasArgs<>), I chose to give the Alias
its own Arg object. For convenience, I just store the alias directly in
the unaliased arg – there aren't many arg objects at runtime, so that
seems ok.
Finally, I changed Arg::getAsString() to use the alias's representation
if it's present – that function was already documented as being the
suitable function for diagnostics, and most callers already used it for
diagnostics.
Implementation-wise, Arg::accept() previously used to parse things as
the unaliased option. The core of that switch is now extracted into a
new function acceptInternal() which parses as the _aliased_ option, and
the previously-intermingled unaliasing is now done as an explicit step
afterwards.
(This also changes one place in lld that didn't use getAsString() for
diagnostics, so that that one place now also prints the flag as the user
wrote it, not as it looks after it went through unaliasing.)
Differential Revision: https://reviews.llvm.org/D64253
llvm-svn: 365413
The flag is useful when wanting to create .o files that are independent
from the absolute path to the build directory. -fdebug-prefix-map= can
be used to the same effect, but it requires putting the absolute path
to the build directory on the build command line, so it still requires
the build command line to be dependent on the absolute path of the build
directory. With this flag, "-fdebug-compilation-dir ." makes it so that
both debug info and the compile command itself are independent of the
absolute path of the build directory, which is good for build
determinism (in the sense that the build is independent of which
directory it happens in) and for caching compile results.
(The tradeoff is that the debugger needs explicit configuration to know
the build directory. See also http://dwarfstd.org/ShowIssue.php?issue=171130.2)
Differential Revision: https://reviews.llvm.org/D63387
llvm-svn: 363548
Update the `cl` emulation to support the `/Zc:char8_t[-]?` options as per the
MSVC 2019.1 toolset. These are aliases for `-fchar8_t` and `-fno-char8_t`.
llvm-svn: 361859
This is needed so lld-link can find clang_rt.profile when self hosting
on Windows with PGO. Using clang-cl as a linker knows to add the library
but self hosting, using -DCMAKE_LINKER=<...>/lld-link.exe doesn't.
Differential Revision: https://reviews.llvm.org/D61742
llvm-svn: 360674
We will now warn about such options being unused,
which is better than the current
"no such file or directory: '/d2foo'" errors.
Note that we can still handle specific flags separately,
e.g. we were already ignoring /d2FastFail and /d2Zi+
llvm-svn: 355682
The /AI flag is for #using directives, which I don't think we support.
This is consistent with how the /I flag is handled by MSVC. Add a test
for it.
Differential Revision: https://reviews.llvm.org/D57189
llvm-svn: 352119
Summary: /Zc:dllexportInlines with /fallback may cause unexpected linker error. It is better to disallow compile rather than warn for this combination.
Reviewers: hans, thakis
Reviewed By: hans
Subscribers: cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D54426
llvm-svn: 346733
Wang, Pengfei