There are two ways of rendering comments to as. In both cases the comment is equivalent to one space.
Anything from ‘/*’ through the next ‘*/’ is a comment. This means you may not nest these comments.
/* The only way to include a newline ('\n') in a comment is to use this sort of comment. */ /* This sort of comment does not nest. */
Anything from the line comment character to the next newline is considered a comment and is ignored. The line comment character is ‘;’ on the ARC; ‘@’ on the ARM; ‘;’ for the H8/300 family; ‘;’ for the HPPA; ‘#’ on the i386 and x86-64; ‘#’ on the i960; ‘;’ for the PDP-11; ‘;’ for picoJava; ‘#’ for Motorola PowerPC; ‘#’ for IBM S/390; ‘#’ for the Sunplus SCORE; ‘!’ for the Renesas / SuperH SH; ‘!’ on the SPARC; ‘#’ on the ip2k; ‘#’ on the m32c; ‘#’ on the m32r; ‘|’ on the 680x0; ‘#’ on the 68HC11 and 68HC12; ‘#’ on the Vax; ‘;’ for the Z80; ‘!’ for the Z8000; ‘#’ on the V850; ‘#’ for Xtensa systems; see Machine Dependencies.
On some machines there are two different line comment characters. One character only begins a comment if it is the first non-whitespace character on a line, while the other always begins a comment.
The V850 assembler also supports a double dash as starting a comment that extends to the end of the line.
‘--’;
To be compatible with past assemblers, lines that begin with ‘#’ have a special interpretation. Following the ‘#’ should be an absolute expression (see Expressions): the logical line number of the next line. Then a string (see Strings) is allowed: if present it is a new logical file name. The rest of the line, if any, should be whitespace.
If the first non-whitespace characters on the line are not numeric, the line is ignored. (Just like a comment.)
# This is an ordinary comment. # 42-6 "new_file_name" # New logical file name # This is logical line # 36.
This feature is deprecated, and may disappear from future versions of as.