Merge pull request JuliaLang#13506 from stevengj/buildspawn1

eval build.jl files in a separate Julia process for Pkg.build

base/pkg/entry.jl

@@ -725,22 +725,66 @@ function warnbanner(msg...; label="[ WARNING ]", prefix="")
  warn(prefix="", "="^cols)
 end
 
-function build!(pkgs::Vector, errs::Dict, seen::Set=Set())
+function build!(pkgs::Vector, buildstream::IO, seen::Set)
  for pkg in pkgs
  pkg == "julia" && continue
  pkg in seen && continue
- build!(Read.requires_list(pkg),errs,push!(seen,pkg))
+ build!(Read.requires_list(pkg),buildstream,push!(seen,pkg))
  Read.isinstalled(pkg) || throw(PkgError("$pkg is not an installed package"))
  path = abspath(pkg,"deps","build.jl")
  isfile(path) || continue
- info("Building $pkg")
- cd(dirname(path)) do
- try evalfile(path)
- catch err
- warnbanner(err, label="[ ERROR: $pkg ]")
+ println(buildstream, path) # send to build process for evalfile
+ flush(buildstream)
+ end
+end
+
+function build!(pkgs::Vector, errs::Dict, seen::Set=Set())
+ # To isolate the build from the running Julia process, we
+ # execute the build.jl files in a separate process that
+ # is sitting there waiting for paths to evaluate. Errors
+ # are serialized to errfile for later retrieval into errs[pkg]
+ errfile = tempname()
+ close(open(errfile, "w")) # create empty file
+ code = """
+ open("$(escape_string(errfile))", "a") do f
+ for path_ in eachline(STDIN)
+ path = chomp(path_)
+ pkg = basename(dirname(dirname(path)))
+ try
+ info("Building \$pkg")
+ cd(dirname(path)) do
+ evalfile(path)
+ end
+ catch err
+ Base.Pkg.Entry.warnbanner(err, label="[ ERROR: \$pkg ]")
+ serialize(f, pkg)
+ serialize(f, err)
+ end
+ end
+ end
+ """
+ io, pobj = open(detach(`$(Base.julia_cmd())
+ --history-file=no
+ --color=$(Base.have_color ? "yes" : "no")
+ --eval $code`), "w", STDOUT)
+ try
+ build!(pkgs, io, seen)
+ close(io)
+ wait(pobj)
+ success(pobj) || error("Build process failed.")
+ open(errfile, "r") do f
+ while !eof(f)
+ pkg = deserialize(f)
+ err = deserialize(f)
  errs[pkg] = err
  end
  end
+ catch
+ kill(pobj)
+ close(io)
+ rethrow()
+ finally
+ isfile(errfile) && Base.rm(errfile)
  end
 end