restore DEPOT_PATH etc after precompilation workload ran

Author: fatteneder

base/loading.jl

@@ -2303,10 +2303,18 @@ function include_package_for_output(pkg::PkgId, input::String, depot_path::Vecto
     catch ex
         precompilableerror(ex) || rethrow()
         @debug "Aborting `create_expr_cache'" exception=(ErrorException("Declaration of __precompile__(false) not allowed"), catch_backtrace())
-        exit(125) # we define status = 125 means PrecompileableError
+        exit(125) # we define status = 125 means PrecompilableError
     finally
         Core.Compiler.track_newly_inferred.x = false
     end
+
+    # restore some globals in case they were altered in the precompilation workload
+    append!(empty!(Base.DEPOT_PATH), depot_path)
+    append!(empty!(Base.DL_LOAD_PATH), dl_load_path)
+    append!(empty!(Base.LOAD_PATH), load_path)
+    ENV["JULIA_LOAD_PATH"] = join(load_path, Sys.iswindows() ? ';' : ':')
+    set_active_project(nothing)
+
 end
 
 const PRECOMPILE_TRACE_COMPILE = Ref{String}()

doc/src/manual/modules.md

@@ -578,6 +578,8 @@ code to help the user avoid other wrong-behavior situations:
 2. `global const` statements from local scope after `__init__()` has been started (see issue #12010
    for plans to add an error for this)
 3. Replacing a module is a runtime error while doing an incremental precompile.
+4. Any precompilation workload must restore the global variables `DEPOT_PATH, LOAD_PATH, ENV, Base.active_project()`
+   to their initial state at the end of execution.
 
 A few other points to be aware of: