For not-well-understood reasons, ld's `--gc-sections` discards a large number of the PGO bookkeeping structures that enable us to keep track of function counters, and the effect gets worse in object files generated by clang-10.
As much as I'd like to understand this better, the investigations take way too much time. As a path of least resistance, we can disable `--gc-sections` for the instrumentation phase of PGO builds. It won't harm anything since users never see those builds, and it will improve the performance of the optimized phase greatly.
Differential Revision: https://phabricator.services.mozilla.com/D78112
For not-well-understood reasons, ld's `--gc-sections` discards a large number of the PGO bookkeeping structures that enable us to keep track of function counters, and the effect gets worse in object files generated by clang-10.
As much as I'd like to understand this better, the investigations take way too much time. As a path of least resistance, we can disable `--gc-sections` for the instrumentation phase of PGO builds. It won't harm anything since users never see those builds, and it will improve the performance of the optimized phase greatly.
Differential Revision: https://phabricator.services.mozilla.com/D78112
For not-well-understood reasons, ld's `--gc-sections` discards a large number of the PGO bookkeeping structures that enable us to keep track of function counters, and the effect gets worse in object files generated by clang-10.
As much as I'd like to understand this better, the investigations take way too much time. As a path of least resistance, we can disable `--gc-sections` for the instrumentation phase of PGO builds. It won't harm anything since users never see those builds, and it will improve the performance of the optimized phase greatly.
Differential Revision: https://phabricator.services.mozilla.com/D78112
JSAPI functions are not extern "C" anymore. This warning has a couple false
positives due to template specialization (see first patch of this bug), but we
were already working around them, because apparently some mingw builds use it.
Once I fix cbindgen to generate the specializations as needed we can remove
those workarounds, but this is green in the meantime and doesn't hurt.
Depends on D61626
Differential Revision: https://phabricator.services.mozilla.com/D61627
--HG--
extra : moz-landing-system : lando
This is a fairly straightforward port of the AS tool checks from old-configure
to toolchain.configure. AS is a little quirky in that we currently do a
normal-looking check for it, but then override that value to be the C compiler
for non-Windows builds, and ml[64]/armasm64 for Windows builds.
After migrating those checks, the only things left in the MOZ_DEFAULT_COMPILER
macro in compiler-opts.m4 were some unused bits, so I removed them:
* Setting of CPP/CXXCPP, which are set in toolchain.configure now
* Setting HOST_LDFLAGS to empty, which doesn't seem particularly useful.
There was also a quirky old test that the assembler was ml[64] when js-ctypes
is enabled that I removed, I don't think it provides any value since this
patch will ensure that we're using the right assembler for Windows builds.
Last attempt, a few years ago, blatantly failed because nautilus (the
GNOME file manager) can't start PIE executables, which look like shared
libraries, and that it thus considers not being executables.
Downstreams don't actually have the problem, because users won't be
launching Firefox from a file manager, but for mozilla.org builds, it is
a problem because users would download, then extract, and then likely
try to run the Firefox executable from a file manager.
So for mozilla.org builds, we still need to find a way around the
nautilus problem.
A .desktop file could be a solution, but .desktop files have not
actually been designed for this use case, which leads to:
- having to use an awful one-liner shell wrapper to derive the path
to the executable from that of the .desktop file,
- not even being able to associate an icon,
- the .desktop file not being copiable to a location where .desktop
files would normally go, because it would then fail to find the
executable.
Another possibility is to go back to using a shell wrapper, but that's
not entirely appealing.
What we chose here is similar, where we have a small `firefox` wrapper
that launches the real `firefox-bin` (which is still leftover from those
old times where we had a shell wrapper, for reasons).
The small `firefox` wrapper is a minimalist C executable that just
finds the path to the `firefox-bin` executable and executes it with the
same args it was called with. The wrapper is only enabled when the
MOZ_NO_PIE_COMPAT environment variable is set, which we only take into
account on Linux. The variable is only really meant to be used for
mozilla.org builds, for the nautilus problem. Downstreams will just pick
the default, which is changed to build PIE.
On other platforms, PIE was already enabled by default, so we just
remove the --enable-pie configure flag.
Differential Revision: https://phabricator.services.mozilla.com/D5109
Some gaia-related code was also found and removed as part of the
cleanup.
MozReview-Commit-ID: DEjVSljzzu1
--HG--
extra : rebase_source : 58c4c34df44a258d90029853f29ea01338bd142b
Also remove bits of a comment, now that we support only macOS 10.9+, most of the
comment isn't relevant.
While PIE is enabled by default on macOS, this isn't true of clang on Linux.
--enable-pie can now be used with clang on Linux.
r=froydnj
MozReview-Commit-ID: rc6zJiWzLo
--HG--
extra : rebase_source : 3745175e106ea8c6be9271d8135d43ba359434c7
Since bug 1259382, CC and CXX are always set, so we can stop
falling back to cl on Windows, and clang on OSX in compiler-opts.m4.
Also, we were actively rejecting GCC on OSX because it was based on
GCC 4.2 and known to be broken, but that test predates our requirement
for more recent versions of GCC, which would fail configure anyways.
So just remove that GCC test. Building with a modern GCC from macports
or wherever might actually work anyways.
Finally, remove target bit-width mismatch with the compiler as it's
handled in python configure since bug 1288313.
--HG--
extra : rebase_source : 9968028cc4e9c197b72136037a7298be10cc139a
Python configure is already checking that the C++ compiler is indeed a C++
compiler, no need to double check in old-configure.
--HG--
extra : rebase_source : fcb6fc7ac88dcf3ef172cd30e23454b654e08c03
Setting MOZ_DEBUG_SYMBOLS as a define was not moved, as this value is not
checked, and exporting MOZ_DEBUG_SYMBOLS was not moved, as this would only
impact nspr, and we're no longer using the nspr build system.
MozReview-Commit-ID: EvBTunhxcsr
- DEVELOPER_OPTIONS, INTEL_CC, INTEL_CXX, MOZ_ENABLE_QTMOBILITY,
GTK_CONFIG are or even were never used outside configure.
- MOZ_PROFILELOCKING which gradually became a no-op over the years. This
also removes the configure flag that sets it.
- XULRUNNER_STUB_NAME is xulrunner-only, and xulrunner is gone. This
also removes the configure flag that sets it.
- The only use of MOZ_CAN_RUN_PROGRAMS was removed in bug 780561.
- AR_LIST and AR_DELETE have not been used since bug 584474.
- MOZ_COMPONENT_NSPR_LIBS is leftover from bug 1036894.
- MOZ_PNG_ARM_NEON_CHECK is not used since bug 980488.
- MOZ_WEBRTC_LEAKING_TESTS has been no-oped by bug 825510.
- VPX_NEED_OBJ_INT_EXTRACT and NO_INTEGRATED_AS_CFLAGS are not used since
bug 1151175.
- WCHAR_CFLAGS is not used since bug 904985.
compiler-opts.m4's check for `MOZ_CXX_SUPPORTS_WARNING(-W, unreachable-code-return, ac_cxx_has_wunreachable_code_return)` is broken. The C/C++ code that configure emits for MOZ_CXX_SUPPORTS_WARNING() actually contains a -Wunreachable-code-return warning and, thus, doesn't actually detect that clang supports the -Wunreachable-code-return flag.
This configure code in MOZ_CXX_SUPPORTS_WARNING():
AC_TRY_COMPILE([],
[return(0);],
$3="yes",
$3="no")
generates something like:
int main() {
return(0);
; return 0; }
where the second return, automatically emitted by configure, is unreachable and causes a -Wunreachable-code-return warning.
The fix is to remove the redundant return(0) from MOZ_CXX_SUPPORTS_WARNING(). This allows clang's -Wunreachable-code-return flag to be detected, but then -Wunreachable-code-return breaks other configure checks, including third-party libraries' configure checks (in particular jemalloc) that also have redundant `return(0)`. So all the third-party libraries' configure checks would need to be fixed upstream, which seems like more hassle than the value of the -Wunreachable-code-return warnings.
-Wno-psabi has not been necessary since we updated the build machines to Android NDK r8c three years ago in bug 826133.
-Wsometimes-initialized is not necessary because it is implicitly enabled by clang's -Wuninitialized, which is enable by -Wall.
-Wcast-align is very noisy and we apparently only enable it for gcc on 32-bit x86 builds?
-Wno-unused-local-typedef is no longer necessary. This is the clang flag; gcc's flag is -Wno-unused-local-typedefs, with an 's'. Suppressing gcc's warning was recently deemed unnecessary and WONTFIX'd in bug 1243604. Unsurprisingly, we no longer need it on clang either.
-Wrange-loop-analysis is no longer necessary because it is implicitly enabled by -Wloop-analysis, which is enabled by the previous commit.
-Wsign-compare is enabled by gcc's -Wall (for C++ only), but not by clang's -Wall. -Wsign-compare is enabled for C and C++ by gcc's -Wextra and clang's -Wextra, which we don't use.
The flags added in toolkit/locales/Makefile.in turn out not to be actually
used, so just remove that.
The remaining uses of XULPPFLAGS are to set debug flags depending on whether
MOZ_DEBUG is set or not. Just set a dedicated variable with the right value
from configure.
Mike Hommey
David Major
Narcis Beleuzu
Razvan Maries
Bogdan Tara
Ricky Stewart
Emilio Cobos Álvarez
Tom Ritter
Cosmin Sabou
Nathan Froyd
Gregory Szorc
Sylvestre Ledru
Mike Hommey
Alex Gaynor
Jim Blandy
Kris Maglione
Chris Manchester
Chris Peterson
Ryan VanderMeulen