Different file sizes for program compiled with 'rustc' and 'rustc +stage1'

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Hello there.
I have a Rust compiler (version 1.68.2) installed. Recently I also build the Rust compiler from source (version 1.70.0-dev) using the command ./x.py build library.

Now when I compile a simple Rust program with rustc, and then compile the same program using my build compiler with rustc +stage1, the two executables vary significantly in file size and amount of included functions.
When compiling with rustc +stage1 and using a disassembler, it shows that it contains 1456 functions, as opposed to 652 functions when using rustc.

I know that the stage1 compiler is not the full rustc build, and that one can build a stage2 compiler wich is considered the full rustc build. Now my question is, can I expect to produce executables that are close to rustc compiled executables (in file size and included functions) just by using the stage2 compiler? Or is there something else to consider?

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One significant difference is that the distributed compiler is built with a single codegen unit (CGU), but the default for a local build leaves it to rustc defaults. This is the same for stage1 and "full" later-stage builds. You can set codegen-units-std = 1 in your config.toml to get closer to the distributed builds, even for stage1.

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