test$ test$ cat test.asm [map brief _MAP] section FOO times 16 nop section BAR test$ nasm -v NASM version 2.16.02rc2 compiled on Oct 12 2023 test$ nasm test.asm -D_MAP=stderr - NASM Map file --------------------------------------------------------------- Source file: test.asm Output file: test -- Program origin ------------------------------------------------------------- 00000000 -- Sections (summary) --------------------------------------------------------- Vstart Start Stop Length Class Name 0 0 0 00000000 progbits .text 0 0 10 00000010 progbits FOO 10 10 10 00000000 progbits BAR test$ nasm test.asm -D_MAP=stdout - NASM Map file --------------------------------------------------------------- Source file: test.asm Output file: test -- Program origin ------------------------------------------------------------- 00000000 -- Sections (summary) --------------------------------------------------------- Vstart Start Stop Length Class Name 0 0 0 00000000 progbits .text 0 0 10 00000010 progbits FOO 10 10 10 00000000 progbits BAR test$ nasm test.asm -D_MAP=test.lst test$ rm test.lst test$ nasm test.asm -D_MAP=quux/test.lst test$ ls test test.asm test$ ~/proj/nasmtest/patch/nasm -v NASM version 2.17rc0 compiled on Sep 3 2025 test$ ~/proj/nasmtest/patch/nasm test.asm -D_MAP=stderr - NASM Map file --------------------------------------------------------------- Source file: test.asm Output file: test -- Program origin ------------------------------------------------------------- 00000000 -- Sections (summary) --------------------------------------------------------- Vstart Start Stop Length Class Name 0 0 0 00000000 progbits .text 0 0 10 00000010 progbits FOO 10 10 10 00000000 progbits BAR test$ ~/proj/nasmtest/patch/nasm test.asm -D_MAP=stdout - NASM Map file --------------------------------------------------------------- Source file: test.asm Output file: test -- Program origin ------------------------------------------------------------- 00000000 -- Sections (summary) --------------------------------------------------------- Vstart Start Stop Length Class Name 0 0 0 00000000 progbits .text 0 0 10 00000010 progbits FOO 10 10 10 00000000 progbits BAR test$ ~/proj/nasmtest/patch/nasm test.asm -D_MAP=test.lst test$ rm test.lst test$ ~/proj/nasmtest/patch/nasm test.asm -D_MAP=quux/test.lst test$ ls test test.asm test$