[lr-dosbox] Unable to install/compile: /home/pi/RetroPie-Setup/tmp/build/lr-dosbox/dosbox_libretro.so not found

[SuperFromND]

Update: I have since sent and merged a PR that fixes this issue.

Log file: https://hastebin.com/ikocalikax.xml
RetroPie version: 4.4
Hardware: Raspberry Pi 3 Model B [not to be confused with the 3B+]

I've attempted to compile lr-dosbox at least twice, and every time it give me this error. The piece of code responsible for the error appears to be with lr-dosbox's code itself:

In file included from src/misc/cross.cpp:30:0:
src/misc/../../libretro/libretro.h:1272:8: error: redefinition of ‘struct retro_midi_interface’
 struct retro_midi_interface
        ^~~~~~~~~~~~~~~~~~~~
src/misc/../../libretro/libretro.h:1213:8: error: previous definition of ‘struct retro_midi_interface’
 struct retro_midi_interface
        ^~~~~~~~~~~~~~~~~~~~
Makefile.libretro:189: recipe for target 'src/misc/cross.o' failed
make: *** [src/misc/cross.o] Error 1
make: *** Waiting for unfinished jobs....
/home/pi
Could not successfully build lr-dosbox - DOS emulator (/home/pi/RetroPie-Setup/tmp/build/lr-dosbox/dosbox_libretro.so not found).

Anyone know of a fix?

[SuperFromND]

Update: I found the culprit! Turns out that the file libretro.h had this struct definition twice:

struct retro_midi_interface
{
   retro_midi_input_enabled_t input_enabled;
   retro_midi_output_enabled_t output_enabled;
   retro_midi_read_t read;
   retro_midi_write_t write;
   retro_midi_flush_t flush;
};

This confused make since you can't redefine a struct once you declare it, causing errors and an eventual crash. Removing one of the struct definitions appears to have fixed this issue.