use a Threads.Atomic counter instead

base/Base.jl

@@ -488,7 +488,6 @@ function __init__()
  if haskey(ENV, "JULIA_MAX_NUM_PRECOMPILE_FILES")
  MAX_NUM_PRECOMPILE_FILES[] = parse(Int, ENV["JULIA_MAX_NUM_PRECOMPILE_FILES"])
  end
- append!(empty!(TIMING_IMPORTS), zeros(Int, Threads.nthreads()))
  nothing
 end
 

base/loading.jl

@@ -822,7 +822,7 @@ function _require_from_serialized(path::String)
 end
 
 # use an Int counter so that nested @time_imports calls all remain open
-const TIMING_IMPORTS = Int[] # initialized in __init__
+const TIMING_IMPORTS = Threads.Atomic{Int}(0)
 
 # returns `true` if require found a precompile cache for this sourcepath, but couldn't load it
 # returns `false` if the module isn't known to be precompilable
@@ -859,7 +859,7 @@ function _require_search_from_serialized(pkg::PkgId, sourcepath::String, depth::
  if isa(restored, Exception)
  @debug "Deserialization checks failed while attempting to load cache from $path_to_try" exception=restored
  else
- if TIMING_IMPORTS[Threads.threadid()] > 0
+ if TIMING_IMPORTS[] > 0
  elapsed = round((time_ns() - t_before) / 1e6, digits = 1)
  tree_prefix = depth == 0 ? "" : "$(" "^(depth-1))┌ "
  print("$(lpad(elapsed, 9)) ms ")

stdlib/InteractiveUtils/src/macros.jl

@@ -235,10 +235,10 @@ end
 macro time_imports(ex)
  quote
  try
- Base.TIMING_IMPORTS[Threads.threadid()] += 1
+ Base.TIMING_IMPORTS[] += 1
  $(esc(ex))
  finally
- Base.TIMING_IMPORTS[Threads.threadid()] -= 1
+ Base.TIMING_IMPORTS[] -= 1
  end
  end
 end