compile FastBuild with UnrealEngine patch on Ubuntu20.04 (these commands are meant to be run manually on a terminal)

gistfile1.txt

# compile FastBuild with UnrealEngine patch on Ubuntu20.04 (these commands are meant to be run manually on a terminal)
# check what fbuild patch version is required at: ./Engine/Extras/ThirdPartyNotUE/FASTBuild/*.diff #ex.: 0.99
strPath="`pwd`/Engine/Extras/ThirdPartyNotUE/FASTBuild/Linux/dist_v0.99/" # download and extract fbuild sorce code to a folder like this
cd "$strPath"
chmod -vR u+w * # make it sure the extracted files all have write permission!
patch --binary -p 1 <../../fbuild_0.99.diff # I think this file was downloaded from somewhere by Setup.sh or GenerateProjectFiles.sh or may be thru make (mono), as I cant find it's origin to report the bug at the end of this text about FBuildCoordinator.bff
sudo apt install clang g++-7
#$head "$strPath/External/SDK/Clang/Linux/Clang6.bff"
sed -i -r "s@(^.Clang6_BasePath = ').*(')@\1$(dirname $(which clang))\2@" "$strPath/External/SDK/Clang/Linux/Clang6.bff" # to match installed clang
#$head "$strPath/External/SDK/Clang/Linux/Clang6.bff"
cd "$strPath/Code"
chmod +x ../Bin/Linux-x64/fbuild
# run fbuild below.
#  there may have dependencies like clang and g++-7 that you will need to install on your OS. 
#  If it fails in the end, run it again a few times until you see a `ld` complaint about missing libraries ex.: -lFuzzer,-lc++,-lc++abi,-lunwind. 
#  ForUbuntu20.04: Unwind indirectly need this: https://ubuntu.pkgs.org/20.04/ubuntu-updates-main-amd64/liblzma-dev_5.2.4-1ubuntu1_amd64.deb.html (not present on ubuntu repositories) as liblzma5_5.2.4-1_amd64.deb cannot replace liblzma5_5.2.4-1ubuntu1 package w/o breaking a lot of things... 
#  sudo apt install libc++abi-dev libunwind-dev libfuzzer-10-dev libfuzzer-10-dev #liblzma-dev
../Bin/Linux-x64/fbuild # add -verbose to help
#(OPTIONAL) if libfuzzer-10-dev give code compilation errors like "undefined reference":
  sed -i -r "s@(ExtraLinkerOptions_MSan = '.*)(')@\1 -lstdc++\2@" "$strPath/Code/Tools/FBuild/BFFFuzzer/BFFFuzzer.bff"
  ../Bin/Linux-x64/fbuild
#(OPTIONAL) if you built the specific fuzzer version explained at: ./Engine/Extras/ThirdPartyNotUE/FASTBuild/Linux/dist_v0.99/Code/Tools/FBuild/BFFFuzzer/README.md
  LIBRARY_PATH="$LD_LIBRARY_PATH:$strPath/../llvm-5.0.0.src/lib/Fuzzer";../Bin/Linux-x64/fbuild # it IS LIBRARY_PATH not LD_LIBRARY_PATH
  ../Bin/Linux-x64/fbuild
#(OPTIONAL) error: objcopy: '../tmp/x64ClangLinux-Release/ToolsFBuildFBuildCoordinator/fbuildcoordinator': No such file
  #change in the FBuildCoordinator.bff file: `.ProjectPath        = 'Tools\FBuild\FBuildCoordinator'` to `.ProjectPath        = 'Tools/FBuild/FBuildCoordinator'`
  # OR follow the hardest newbie path:
  ../Bin/Linux-x64/fbuild -verbose #to see the malignous "\": /bin/bash -c "objcopy --only-keep-debug ../tmp/x64ClangLinux-Release/Tools\FBuild\FBuildCoordinator/fbuildcoordinator ../tmp/x64ClangLinux-Release/Tools\FBuild\FBuildCoordinator/fbuildcoordinator.debug && objcopy --strip-debug ../tmp/x64ClangLinux-Release/Tools\FBuild\FBuildCoordinator/fbuildcoordinator && objcopy --add-gnu-debuglink ../tmp/x64ClangLinux-Release/Tools\FBuild\FBuildCoordinator/fbuildcoordinator.debug ../tmp/x64ClangLinux-Release/Tools\FBuild\FBuildCoordinator/fbuildcoordinator"
  egrep "objcopy" ../* -rnI #see files that need patching
  FUNChope() { echo -E "PROBLEM(WrongBackslash): $@";acmd=();while ! ${1+false};do acmd+=($(echo "$1" |sed -r 's"[\]"/"g'));shift&&:;done; declare -p acmd; set -x; "${acmd[@]}"; set +x; };export -f FUNChope; #brings hope
  sed -i -r -e "s@'objcopy@'FUNChope objcopy@" -e '/objcopy/ s@([$]LinkerOutput[$])@"\1"@g' ../Code/Tools/FBuild/FBuildCoordinator/FBuildCoordinator.bff #fix the file (is there a better way?)
  ../Bin/Linux-x64/fbuild

did someone found out how fbuild_0.99.diff is generated? where it comes from? I would like to submit a patch for linux.

did someone found out how fbuild_0.99.diff is generated? where it comes from? I would like to submit a patch for linux.

Well Epic Games are developing the engine using perforce, and the diff is the file with their perforce changes.
We mere mortals have no access to it.