mirror of
https://github.com/ValveSoftware/Proton.git
synced 2024-10-16 15:26:59 +03:00
build-mingw-w64.sh: Document my findings
This commit is contained in:
Andrew Eikum
parent
2ba034409c
commit
3454fff8d3
@ -2,10 +2,127 @@
|
||||
|
||||
set -e
|
||||
|
||||
# The Story So Far
|
||||
#
|
||||
# We need two cross-compilers to build Proton. These each have to run in the
|
||||
# Steam runtimes, each of which only supports 32- or 64-bit programs. Our build
|
||||
# VM is a 64-bit Linux machine. So our platform configurations are:
|
||||
#
|
||||
# 64-bit cross-compiler:
|
||||
# Build (where the compiler is built): 64-bit linux (our VM)
|
||||
# Host (where the compiler is run): 64-bit linux (64-bit Steam runtime)
|
||||
# Target (what the compiler outputs): 64-bit win32 (PE files to be run)
|
||||
#
|
||||
# 32-bit cross-compiler:
|
||||
# Build (where the compiler is built): 64-bit linux (our VM)
|
||||
# Host (where the compiler is run): 32-bit linux (32-bit Steam runtime)
|
||||
# Target (what the compiler outputs): 32-bit win32 (PE files to be run)
|
||||
#
|
||||
# The former is a pretty standard cross-compiler setup.
|
||||
#
|
||||
# gcc calls the latter, where all of the platforms are different, a "Canadian"
|
||||
# build. See "The GNU configure and build system" by Ian Lance Taylor, section
|
||||
# "Canadian Cross", available here:
|
||||
# https://www.airs.com/ian/configure/configure_6.html
|
||||
#
|
||||
# This turned out to be quite difficult, possibly due to the added complexity of
|
||||
# mingw-w64. I'm documenting the problems I had and how I solved/worked around
|
||||
# them here, to hopefully save myself or someone else some heartburn in the
|
||||
# future. If you are a compiler expert and find yourself shaking your head at
|
||||
# this poor fool, I welcome your assistance improving this.
|
||||
#
|
||||
# Canadian builds require the build machine to already have a cross-compiler for
|
||||
# the Target platform available on the Build machine. Without this, the gcc build
|
||||
# will fail with:
|
||||
#
|
||||
# i686-w64-mingw32-gcc -dumpspecs > tmp-specs
|
||||
# /bin/bash: i686-w64-mingw32-gcc: command not found
|
||||
#
|
||||
# We are building both C and C++ lang support, so we need both gcc and g++
|
||||
# cross-compilers available. With the Build->Target cross-compilers installed,
|
||||
# we can now build gcc, and use that to build mingw-w64. After that, we need to
|
||||
# build gcc's libraries, like libgcc and libstdc++v3, against those mingw-w64
|
||||
# libraries. However, the libatomic and/or libgomp builds will fail with:
|
||||
#
|
||||
# checking for suffix of object files...
|
||||
# configure: error: in `/home/vagrant/mingw/build-i686-w64-mingw32/gcc/i686-w64-mingw32/libatomic':
|
||||
# configure: error: C compiler cannot create executables
|
||||
# See `config.log' for more details
|
||||
#
|
||||
# checking for suffix of object files...
|
||||
# configure: error: in `/home/vagrant/mingw/build-i686-w64-mingw32/gcc/i686-w64-mingw32/libgomp':
|
||||
# configure: error: C compiler cannot create executables
|
||||
# See `config.log' for more details
|
||||
#
|
||||
# Digging into config.log shows it can't find libgcc:
|
||||
#
|
||||
# configure:3722: checking whether the C compiler works
|
||||
# configure:3744: i686-w64-mingw32-gcc -L/home/vagrant/mingw/output/i686-w64-mingw32/lib -L/home/vagrant/mingw/output/mingw/lib -isystem /home/vagrant/mingw/output/i686-w64-mingw32/include -isystem /home/vagrant/mingw/output/mingw/include -g -O2 conftest.c >&5
|
||||
# /home/vagrant/mingw/output/lib/gcc/i686-w64-mingw32/9.2.0/../../../../i686-w64-mingw32/bin/ld: cannot find -lgcc
|
||||
# /home/vagrant/mingw/output/lib/gcc/i686-w64-mingw32/9.2.0/../../../../i686-w64-mingw32/bin/ld: cannot find -lgcc_eh
|
||||
# /home/vagrant/mingw/output/lib/gcc/i686-w64-mingw32/9.2.0/../../../../i686-w64-mingw32/bin/ld: cannot find -lgcc
|
||||
# /home/vagrant/mingw/output/lib/gcc/i686-w64-mingw32/9.2.0/../../../../i686-w64-mingw32/bin/ld: cannot find -lgcc_eh
|
||||
# collect2: error: ld returned 1 exit status
|
||||
#
|
||||
# I don't know what causes this (maybe Canadian builds don't like being split up
|
||||
# like this?). However, installing libgcc explicitly first will work around it.
|
||||
# After installing libgcc explicitly, we can then build the rest of gcc's
|
||||
# libraries. That was all the easy (ha!) stuff. At this point, you will have a
|
||||
# cross-compiler that will build Proton.
|
||||
#
|
||||
# However, there's a sneaky problem. For some reason the libstdc++v3 build system
|
||||
# requires libstdc++ to be available to detect C-lang functions(?!?). It will
|
||||
# still build without those C functions, but it may have far worse performance
|
||||
# (see Proton github issue #3198). You can detect this situation by examining the
|
||||
# config.log output for libstdc++v3 after your build completes:
|
||||
#
|
||||
# configure:16811: checking for gettimeofday
|
||||
# configure:16827: checking sys/time.h usability
|
||||
# configure:16827: i686-w64-mingw32-c++ -L/home/vagrant/mingw/output/i686-w64-mingw32/lib -L/home/vagrant/mingw/output/mingw/lib -isystem /home/vagrant/mingw/output/i686-w64-mingw32/include -isystem /home/vagrant/mingw/output/mingw/include -c -g -O2 -fno-exceptions conftest.cpp >&5
|
||||
# configure:16827: $? = 0
|
||||
# configure:16827: result: yes
|
||||
# configure:16827: checking sys/time.h presence
|
||||
# configure:16827: i686-w64-mingw32-c++ -L/home/vagrant/mingw/output/i686-w64-mingw32/lib -L/home/vagrant/mingw/output/mingw/lib -isystem /home/vagrant/mingw/output/i686-w64-mingw32/include -isystem /home/vagrant/mingw/output/mingw/include -E conftest.cpp
|
||||
# configure:16827: $? = 0
|
||||
# configure:16827: result: yes
|
||||
# configure:16827: checking for sys/time.h
|
||||
# configure:16827: result: yes
|
||||
# configure:16840: checking for gettimeofday
|
||||
# configure:16875: i686-w64-mingw32-c++ -L/home/vagrant/mingw/output/i686-w64-mingw32/lib -L/home/vagrant/mingw/output/mingw/lib -isystem /home/vagrant/mingw/output/i686-w64-mingw32/include -isystem /home/vagrant/mingw/output/mingw/include -o conftest.exe -g -O2 -fno-exceptions conftest.cpp >&5
|
||||
# /home/vagrant/mingw/output/lib/gcc/i686-w64-mingw32/9.2.0/../../../../i686-w64-mingw32/bin/ld: cannot find -lstdc++
|
||||
# collect2: error: ld returned 1 exit status
|
||||
#
|
||||
# But that error doesn't kill configure, and it happily continues with this in
|
||||
# config.h:
|
||||
#
|
||||
# /* #undef _GLIBCXX_USE_GETTIMEOFDAY */
|
||||
#
|
||||
# This triggers the bad codepath in libstdc++v3 that caused the performance
|
||||
# problem mentioned above, and is clearly wrong anyway, as gettimeofday is
|
||||
# definitely available. Yes, this was a huge pain to puzzle out. I "solved" this
|
||||
# by letting the libstdc++v3 build continue, then re-running the build after
|
||||
# installing it, so now it will find libstdc++ and so correctly detect the C-lang
|
||||
# function that has nothing at all to do with libstdc++. Argh.
|
||||
#
|
||||
# After all that, we finally have a functioning set of cross-compilers. Most of
|
||||
# the configuration parameters used here are taken from the Arch Linux mingw-w64
|
||||
# PKGBUILDs, as those were written by someone with more knowledge than me, and
|
||||
# have had a lot of testing. We make one tweak to the gcc configuration, which is
|
||||
# to disable SJLJ exceptions and enable DWARF2 debug symbols. The former
|
||||
# apparently helps with performance on 32-bit, and the latter puts debug symbols
|
||||
# in a format that more Linux tooling can read.
|
||||
#
|
||||
# Side note, the Arch Linux PKGBUILDs work very differently from how this script
|
||||
# works. While working on this, I tried to adapt the PKGBUILDs' process here
|
||||
# (e.g. build a bootstrap C-lang compiler, use that to build mingw-w64, then
|
||||
# rebuild gcc against the mingw-w64 CRT with C++-lang support), but I ran into a
|
||||
# ton of problems, possibly caused by the Canadian-ness of the build, and
|
||||
# eventually ran out of ideas for working around them.
|
||||
|
||||
if [ -z "$1" ]; then
|
||||
echo "Makes a local build of mingw-w64 in this directory and installs it to the given path."
|
||||
echo ""
|
||||
echo "Note: Requires a system mingw-w64 to be present already, for us to bootstrap with."
|
||||
echo "Note: Requires a system mingw-w64 compiler to be present already on your build machine, for us to bootstrap with."
|
||||
echo ""
|
||||
echo "usage:"
|
||||
echo -e "\t$0 <installation path e.g. \$HOME/.local>"
|
||||
@ -175,7 +292,7 @@ function build_arch {
|
||||
|
||||
pushd gcc/
|
||||
#next step requires libgcc in default library location, but
|
||||
#"canadian" build doesn't handle that, so install it explicitly
|
||||
#"canadian" build doesn't handle that(?), so install it explicitly
|
||||
PATH=$NEWPATH make configure-target-libgcc
|
||||
PATH=$NEWPATH make -C $WIN32_TARGET_ARCH/libgcc $JOBS
|
||||
PATH=$NEWPATH make -C $WIN32_TARGET_ARCH/libgcc $JOBS install
|
||||
|
||||
Loading…
Reference in New Issue
Block a user