Question: Creating custom image

I tried to create a custom image, but I got this error:

```
ERROR: The following 5 direct dependencies failed to precompile:

JuMP [4076af6c-e467-56ae-b986-b466b2749572]

Error: Missing source file for JuMP [4076af6c-e467-56ae-b986-b466b2749572]
PackageCompiler [9b87118b-4619-50d2-8e1e-99f35a4d4d9d]

Error: Missing source file for PackageCompiler [9b87118b-4619-50d2-8e1e-99f35a4d4d9d]
```

I used `--compiler-env` to use my current environment where all those packages are added. but that didn't help either.

I even tried

```
PackageCompiler.create_sysimage(
["JuMP"],
sysimage_path = "customimage." * Libdl.dlext,
precompile_execution_file = "my_test.jl",
)

PackageCompiler.create_sysimage(
[:PyCall];
sysimage_path = "sys.so",
base_sysimage="customimage.so",
)

```
which created `sys.so` but I got core-dump when I used `jl = Julia(sysimage="sys.so")`

Begin with the PackageCompiler.create_sysimage calls and the Julia(sysimage="sys.so") launch shown in the report. Reproduce the missing-source-file errors and core dump using the stated custom-image workflow; done means the failure is narrowed to a reproducible configuration or clearly documented incompatibility.

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