[MLton] cmcat has CM warning messages in output

[Stephen Weeks]

Is there any way to turn off the warning messages produced by cmcat
that unfortunately appear in the file list?  For example, when making
mlyacc.cm, I got the following junk.

src/utils.sig:4.1-4.19 Warning: definition not tracked by CM
src/utils.sml:4.1-4.19 Warning: definition not tracked by CM
src/sigs.sml:4.1-4.19 Warning: definition not tracked by CM
src/hdr.sml:4.1-4.19 Warning: definition not tracked by CM
src/yacc.lex.sml:1.1-1.19 Warning: definition not tracked by CM
src/mklrtable.sml:4.1-4.19 Warning: definition not tracked by CM
src/shrink.sml:4.1-4.19 Warning: definition not tracked by CM
src/verbose.sml:4.1-4.19 Warning: definition not tracked by CM
src/absyn.sig:4.1-4.19 Warning: definition not tracked by CM
src/yacc.sml:4.1-4.19 Warning: definition not tracked by CM