Assemble Problem with FMUL and FADD
ID Number:  Q11343

4.00
MS-DOS
buglist4.00 fixlist5.00 

Problem:

MASM assembles the following instructions, which are incorrect and
should be flagged as errors: 

   fmul    st(1), st(1)
   fadd    st(2), st(1)

Response:

The instructions are invalid and should not be assembled. The
instructions are being assembled as if the second argument were "st",
which would make them valid mnemonics, as the following ".lst" shows: 

   9B DC C9        fmul    st(1), st
   9B DC CA        fmul    st(2), st
   9B DC C1        fadd    st(1), st

   9B DC C9        fmul    st(1), st(1)
   9B DC CA        fmul    st(2), st(1)
   9B DC C1        fadd    st(1), st(2)

Microsoft has confirmed this to be a problem in Version 4.00. This
problem was corrected in Version 5.00.
