.ds RH Implementation Restrictions
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Implementation Restrictions 
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Implementation Restrictions
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GCT should be portable to any UNIX system derived from either
Berkeley 4.X UNIX or System V Release 3 (or later).  It has also been
ported to Apollo Sr10.3.  The tool was implemented by modifying the
GNU C compiler so that it produces new C code instead of object code.
Any C language text accepted by that compiler can be instrumented,
except for these restrictions:
.IP\(bu
The following global identifiers are reserved: Gct_table, Gct_group_table,
Gct_table_size, Gct_num_flags, Gct_current_index, 
gct_writelog, and
gct_readlog.
.IP\(bu
There can be no more than 100,000,000 instrumentation points in the
program.
