@Renetrox said in Can't install RetroArch from Source - orange pi 3 lts:
gfx/drivers/sdl2_gfx.c:542:13: warning: ‘sdl2_gfx_suspend_screensaver’ defined but not used [-Wunused-function]
542 | static bool sdl2_gfx_suspend_screensaver(void data, bool enable) { return false; }
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
CC gfx/common/sdl2_common.c
gfx/common/sdl2_common.c: In function ‘sdl2_set_handles’:
gfx/common/sdl2_common.c:55:55: error: ‘union <anonymous>’ has no member named ‘x11’
55 | video_driver_display_set((uintptr_t)info.info.x11.display);
| ^
This looks suspiciously similar to https://github.com/libretro/RetroArch/issues/9583. In addition to the info requested above, can you confirm whether your SDL2 package is the one from your distro (which one are you using ?) or you are using the RetroPie SDL2 package ?
Post the output of the command: