jca@pnet01.cts.com (John C. Archambeau) (04/29/89)
I posted previously that I seemed to have found a bug in Turbo C 1.5, well I
called Borland's Tech Hotline the other day and I was amazed, but relieved to
find out that the problem wasn't with Turbo C, but with the assembler I was
using for the assembler modules that were linked in with the C code. The
problem is with A86, since A86 doesn't support the convient assume directive
that's found in MASM, you have to explicitly initialize segments, here's why:
In all switch code in Turbo C 1.5, there is this one statement in assembly
code:
jmp word ptr cs:[bx+(some offset)]
Since A86 doesn't initialize segments implicitly (as MASM does), cs is set to
some random value at link time. Because of this, at runtime, you are given
the illusion that the compiler is at fault when in fact it's not. So when
using an assembler that's not 100% MASM compatable, beware. When dealing with
C and assembler the "it's your funeral" philosophy definately applies. I
probably should have known this before, since there are a lot of caveats with
using A86 over MASM. My thanks to Borland for being nice about handling the
situation when I called and pointing me towards the real problem. It
reaffirms my faith in Borland's compilers, but it definately gives me
something to grumble about when it comes to the A86 assembler. It might be
the fastest 80x86 assembler out there, but it has something to be desired with
compatability (quite a bit actually).
JCA
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INET: jca@pnet01.cts.comsmvorkoetter@watmum.waterloo.edu (Stefan M. Vorkoetter) (04/30/89)
In article <4139@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes: >... but it definately gives me >something to grumble about when it comes to the A86 assembler. It might be >the fastest 80x86 assembler out there, but it has something to be desired with >compatability (quite a bit actually). The way I see it, it is MASM's fault (and TC's) for not being compatible with A86. I find A86 much easier to use than MASM. Just my $2 worth. Stefan