From 721932d713e7b6af589207b099d4f341a33f9d34 Mon Sep 17 00:00:00 2001
From: Kristoffer Carlsson <kcarlsson89@gmail.com>
Date: Thu, 23 Sep 2021 20:52:08 +0200
Subject: [PATCH] prevent precompilation from breaking if Base.PkgId is
 imported (#42329)

`repr` will only print a module prefix if the symbol is not existing in Main but the module prefix is unconditionally needed here since the code will be evaluated in another process.
---
 base/loading.jl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/base/loading.jl b/base/loading.jl
index a87a6ed7423c5..b8b998f7a80b6 100644
--- a/base/loading.jl
+++ b/base/loading.jl
@@ -1356,8 +1356,8 @@ function create_expr_cache(pkg::PkgId, input::String, output::String, concrete_d
     for (pkg, build_id) in concrete_deps
         push!(deps_strs, "$(pkg_str(pkg)) => $(repr(build_id))")
     end
-    deps = repr(eltype(concrete_deps)) * "[" * join(deps_strs, ",") * "]"
-
+    deps_eltype = sprint(show, eltype(concrete_deps); context = :module=>nothing)
+    deps = deps_eltype * "[" * join(deps_strs, ",") * "]"
     trace = isassigned(PRECOMPILE_TRACE_COMPILE) ? `--trace-compile=$(PRECOMPILE_TRACE_COMPILE[])` : ``
     io = open(pipeline(`$(julia_cmd()::Cmd) -O0
                        --output-ji $output --output-incremental=yes