gcc mingw-w64 build instructions v2.txt

 1) Disable McAfee's (or any other antivirus) Real Time Scanning
 2) Download msys2-base-x64_86-YYYYMMDD.tar.xz
 3) Unpack it into <msys root dir>
 4) Goto <msys root dir> and double click on msys2.exe, following the instructions on the screen
 5) Run msys2.exe, run `pacman -Syuu` at the msys2 prompt until all the packages are updated
#   {msys2-devel, mingw-w64-i686-toolchain, mingw-w64-x86_64-toolchain} install the necessary gcc later during the building process
 6) `pacman -S base-devel vim`
#   The next set of packages do not need to be installed until when Step 21 (./build --help) is run later
 7) `pacman -S subversion zip p7zip sshpass dejagnu git`
 8) `pacman -Scc` to clean up the install [optional]
 9) `cd /home && mkdir arkay7777`
10) `export HOME=/home/arkay7777` to prevent gcc from being built in some alternate %HOME%
11) `echo $HOME` to test if $HOME is not some alternate %HOME%
12) `cd` into your new $HOME, verify location with `pwd`
#   Use the DEVELOP branch and not the MASTER repository
13) `cd && git clone --branch develop https://github.com/niXman/mingw-builds.git`
#   patch was built via `diff -ur --exclude=toolchains --exclude='*git*' mingw-builds-orig/ mingw-builds/ > '/path/to/gcc mingw-builds.patch'`
#   use `patch --dry-run ...` to test if the patch applies first
14) `cd && patch -uN -p 1 --binary --dry-run --verbose -d mingw-builds/ < '/path/to/gcc mingw-builds.patch'`
15) `ls` to check if <mingw-builds> directory was created
16) `cd /` and `rm /MinGW` if it exists
17) `echo $PATH` to check that the $PATH is not contaminated with another gcc
18) `gcc -v` to also ensure no gcc is on the $PATH
19) `cd && cd mingw-builds`
20) Turn off the power (not display) settings for the computer so that it doesn't go to sleep during the build
21) `./build --help` to determine if (a) all necessary software is available (see Steps 6 and 7) and (b) options for building gcc
#   choose `--mode=gcc-X.Y.Z --rt-version=vN` from the list generated
#   the build process adds the following flags, among others on its own:
#   --cppflags='', --cflags='-O2 -pipe -fno-ident', --cxxflags='-O2 -pipe -fno-ident', --ldflags='-pipe -fno-ident -Wl,--large-address-aware'
#   adding --use-lto causes the build to crash with undefined references to rpl_printf(...) and related IO functions
#   the use of --static-gcc is unnecessary and was used to try to unsuccessfully build with --use-lto
#   building i686 multilib gcc will result in the building of certain i686 and x86_64 libs so always build the i686 gcc first
#   building i686 multilib will download i686 and x86_64 gcc toolchains (e.g. i686-7.2.0-release-posix-sjlj-rt_v5-rev1.7z)
#   into the mingw-builds\toolchains folder as the first step
#   issue with mingw-w64 crt v. 7.0.0: need to add --cflags='<flags>', --cxxflags='<flags>', --ldflags='<flags>' as of mingw-w64 crt v7.0.0
#   due to undefined references to __memcpy_chk and other stack protection functions. Apparently flags such as --ldflags='-lssp' (libssp.a)
#   or, equivalently, --ldflags='-fstack-protector' should help by themselves but I found that they don't. Currently use --cflags until a
#   fix is developed. See https://github.com/msys2/MINGW-packages/issues/5803 for details. Solved with mingw-w64 crt v7.
22) `./build --mode=gcc-10.1.0 --arch=i686 --threads=posix --exceptions=sjlj --enable-languages=c,c++,fortran --rt-version=v7 --jobs=4 --rev=0`
    `./build --mode=gcc-10.1.0 --arch=i686 --threads=win32 --exceptions=sjlj --enable-languages=c,c++,fortran --rt-version=v7 --jobs=4 --rev=0`
    `./build --mode=gcc-10.1.0 --arch=x86_64 --threads=posix --exceptions=seh --enable-languages=c,c++,fortran --rt-version=v7 --jobs=4 --rev=0`
    `./build --mode=gcc-10.1.0 --arch=x86_64 --threads=win32 --exceptions=seh --enable-languages=c,c++,fortran --rt-version=v7 --jobs=4 --rev=0`
23) Wait for ~2-4 hours (i7-6600U) as each build finishes
24) Copy mingw-std-threads for the just-built gcc at path_to_gcc/opt/include/mingw-std-threads. See "mingw-std-threads install.sh" and
    "mingw-std-threads build instructions v2.txt" for how to build these libraries ahead of time. Note that 2 versions need to be created - one
    for i686 and the other for x86_64 builds. Also note that the auto-generated mingw-std-threads C++ headers have version information hardcoded
    into the header and this needs to be edited prior to applying the patch described in "mingw-std-threads build instructions v2.txt".
25) Build boost using the just-built gcc. Change $PATH to use the just-built gcc for building these libraries.
    See "boost build instructions v2.txt". Boost are placed in folders under /opt/include and /opt/lib
26) Turn on the power settings for the computer so that it goes to sleep after 20 minutes
27) Reactivate McAfee's Real Time Scanning
#   use p7zip to compress archives. Find the directory (e.g. mingw-gcc-8.3.0\i686-830-posix-sjlj-rt_v6-rev0\) to compress mingwNN folder
#   -tFormat -m0=Algorithm -mx=CompressionLevel (5 is default, 9 is max i.e. "ultra"), -mfb=# of Fast Bytes (i.e. Word Size),
#   -md=Dictionary Size (32m=32 megabytes), -ms=Set Solid Mode
28) `7za a -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on /c/Users/arkay7777/Desktop/i686-10.1.0-release-posix-sjlj-rt_v7-rev0.7z mingw32`
    `7za a -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on /c/Users/arkay7777/Desktop/i686-10.1.0-release-win32-sjlj-rt_v7-rev0.7z mingw32`
    `7za a -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on /c/Users/arkay7777/Desktop/x86_64-10.1.0-release-posix-seh-rt_v7-rev0.7z mingw64`
    `7za a -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on /c/Users/arkay7777/Desktop/x86_64-10.1.0-release-win32-seh-rt_v7-rev0.7z mingw64`