Emulator

What's the problem? Describe what went wrong.
Old behavior: Add Function renames a single instruction line, does not break original symbol block.
After optimization build: Add function splits a symbol block in half. Cannot load old symbol files correctly.

What steps will reproduce the problem?

Use Right Click -> Add Function on an instruction in the middle of a symbol block in a build before and after 5.0-5475.
Loading a symbol file with single instruction symbols will also turn out incorrectly on bugged builds.

Is the issue present in the latest development version? For future reference, please also write down the version number of the latest development version.

5.0 7767, Issue Present

Is the issue present in the latest stable version?

Not in 5.0.

If the issue isn't present in the latest stable version, which is the first broken version? (You can find the first broken version by bisecting. Windows users can use the tool https://forums.dolphin-emu.org/Thread-green-notice-development-thread-unofficial-dolphin-bisection-tool-for-finding-broken-builds and anyone who is building Dolphin on their own can use git bisect.)

5.0-5475

If your issue is a graphical issue, please attach screenshots and record a three frame fifolog of the issue if possible. Screenshots showing what it is supposed to look like from either console or older builds of Dolphin will help too. For more information on how to use the fifoplayer, please check here: https://wiki.dolphin-emu.org/index.php?title=FifoPlayer

Left: New / Right: Old

I don't know if anyone is relying on the new behavior, but options to change the size of symbol blocks now exist, so you should be able to split a symbol block into two using other methods even if the bug is fixed.