as: W

1 
1 2.17 Control Warnings: '-W', '--warn', '--no-warn', '--fatal-warnings'
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1 
1 'as' should never give a warning or error message when assembling
1 compiler output.  But programs written by people often cause 'as' to
1 give a warning that a particular assumption was made.  All such warnings
1 are directed to the standard error file.
1 
1    If you use the '-W' and '--no-warn' options, no warnings are issued.
1 This only affects the warning messages: it does not change any
1 particular of how 'as' assembles your file.  Errors, which stop the
1 assembly, are still reported.
1 
1    If you use the '--fatal-warnings' option, 'as' considers files that
1 generate warnings to be in error.
1 
1    You can switch these options off again by specifying '--warn', which
1 causes warnings to be output as usual.
1