Date: Wed, 9 Feb 94 14:10:41 CST
From: csaba AT vuse DOT vanderbilt DOT edu (Csaba A. Biegl)
To: beaudot AT tirf DOT grenet DOT fr
Subject: Re:  Compatibility between DJGPP and LibGrx
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu

	From djgpp-bounces AT sun DOT soe DOT clarkson DOT edu Wed Feb  9 10:06:13 1994
	Posted-Date: Wed, 9 Feb 94 11:27:47 +0100
	To: djgpp AT sun DOT soe DOT clarkson DOT edu
	Subject: Compatibility between DJGPP and LibGrx


	I have some problems with go32 V1.10 when I use the LIBGRX (April 1992):

		- The initialization of the graphics mode with a GrSetMode doesn't
		work when I use the Libgrx compiled with the previous version of
		DJGPP.

This has nothing to do with GRX. This is a known bug of GO32 1.10 when
compiled with one of (don't remember which) Turbo C or Borland C. It has
to do with one of these compilers using the CPU registers in such a way
which breaks some inline ASM code. There are fixed 1.10 extenders
available at the usual FTP sites.

		- The graphics primitives (GrPlot, GrLine, ...) crash when I use the
		LibGrx compiled with my current version of DJGPP (gcc V2.42).

Somewhere around GCC version 2.3x something was changed in how GCC
performs optimizations around inline ASM code segments. This broke 
GRX 1.02's (April 1992) 16 color VGA code. As distributed, the 
1.02 version was compiled with GCC 2.2.2, which produced correct
code. If you recompile it with a newer compiler you have to turn
the optimizer off for the 16 color VGA sources (src/p4*.c).
The GRX 1.03 makefile always compiles these modules with the
optimizer off.

	Do I need a more recent version of LibGrx or/and DJGPP?

	Thanks in advance,

		Bill

	--
	 William H.A. Beaudot              E-mail:   beaudot AT tirf DOT grenet DOT fr    
	 Laboratory TIRF - INPG            Position: PhD Student (Neuronics Dept.) 
	 46, avenue Felix Viallet          Phone:    (33) 76 57 48 22
	 38031 GRENOBLE Cedex, FRANCE      Fax:      (33) 76 57 47 90 


Csaba Biegl
csaba AT vuse DOT vanderbilt DOT edu