$ rgrep -I l_ret | grep "l_ret -"
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_agile_rcs.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_agile_rcs_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_mega.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_mega.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_mega_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_mega_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_smart_rcs.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_smart_rcs_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_standard.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_standard_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_turbo.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_dzx7_turbo_back.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_sms_dzx7_standard_vram.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/compress/zx7/z80/asm_sms_dzx7_standard_vram_unsafe.asm: jp c, l_ret - 1
libsrc/_DEVELOPMENT/drivers/tty/state/asm_tty_state_0.asm: jp c, l_ret - 1 ; if printable char
libsrc/_DEVELOPMENT/stdio/z80/asm_fread_unlocked.asm: jp z, l_ret - 1 ; if all records read, return success, hl = nmemb
libsrc/_DEVELOPMENT/string/z80/asm_strset.asm: jp Z,l_ret - 1
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_768.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_768.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_769.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_769.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_772.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_772.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_773.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_773.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_776.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_776.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_777.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_777.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_784.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_784.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_788.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_788.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_792.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_792.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_798.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_798.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_799.asm.m4: jp c, l_ret - 3 ; if read error
libsrc/_DEVELOPMENT/target/zxn/startup/zxn_crt_799.asm.m4: jp nz, l_ret - 3 ; if full amount not read
libsrc/_DEVELOPMENT/env/esxdos/z80/asm_env_getenv.asm: jp z, l_ret - 2 ; if valsz == 0 return length of value string
libsrc/_DEVELOPMENT/env/esxdos/z80/asm_env_tmpnam.asm: jp c, l_ret - 2 ; if open failed exit with hl = template
libsrc/compress/zx7/asm_dzx7_mega.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_mega.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_mega_back.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_mega_back.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_standard.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_standard_back.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_turbo.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_turbo_back.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_agile_rcs.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_agile_rcs_back.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_smart_rcs.asm: jp c, l_ret - 1
libsrc/compress/zx7/asm_dzx7_smart_rcs_back.asm: jp c, l_ret - 1
I'll delete it from the 8085 page 0 implementation.
But seeking comment before extending this further...