why -fno-globals at -O3 with g77

[Jack Howarth]

   A molecular dynamics package, which extensively uses
shared libs and COMMON blocks, has apparently needed to
compile certain files with -fno-globals to build at -O3
with g77 for sometime now. The current g77 3.4 snapshot
of 101503 seems to reduce these down to about 6 fortran
source files. These files will only compile at -O3
when -fno-globals is used. 
   I haven't seen this issue mentioned and was wondering
what the origin of it typically was and if there was
an easy way to avoid tickling this glitch. I ask because
when I removed -fno-globals from all the uneffected source
file compilations the resulting binaries ran about 10%
faster than before.
   Thanks in advance for any insights into this issue.
                    Jack
------------------------------------------------------------------------------
Jack W. Howarth, Ph.D.                                    231 Albert Sabin Way
NMR Facility Director                              Cincinnati, Ohio 45267-0524
Dept. of Molecular Genetics                              phone: (513) 558-4420
Univ. of Cincinnati College of Medicine                    fax: (513) 558-8474