smd@umcp-cs.UUCP (Stanley Dunn) (11/19/85)
Replace this line with your compiler bug I sat down to write the program for the next project I am going to give to my Computer Science I class at home on my CPM system with Turbo Pascal Version 3.00. The following program illustrates the problem with the program I wrote: program junk(input,output); procedure proca(chita:char); forward; procedure procb(chitb:char); begin writeln('Entering procb with a ',chitb); proca('A'); writeln('Leaving procb with a ',chitb); end; procedure proca; begin writeln('Entering proca with a ',chita); if chita = 'I' then procb('I'); writeln('Leaving proca with a ',chita); end; begin proca('I'); end. The output using Turbo Pascal was: Entering proca with a I Entering procb with a I Entering proca with a A Leaving proca with a A Leaving procb with a I Leaving proca with a A While the output for the same program on a VAX with BSD UNIX, IBM VM/SP CMS, or a Macintosh with MacPascal was: Entering proca with a I Entering procb with a I Entering proca with a A Leaving proca with a A Leaving procb with a I Leaving proca with a I as I expected. Calling Borland Technical Support was no help, as they wanted a copy of the program on an IBM format disk. The technical support specialist asked me to send a copy of the program on a disk. When I asked "in what format?" she replied "IBM, of course." I guess CPM does not exist anymore. Obviously, I was quite surprised at the output, and now I wonder how they tested the compiler. It seems that a program as simple as the one above should have been tested. -- Stanley Dunn University of Maryland Department of Computer Science
Reno.wbst@XEROX.ARPA (Jim Reno) (11/20/85)
It is possible that when the technical support person for Borland answered your question the format referred to was the IBM format of sector information that underlies the CPM operating system format on CPM disks. In other words sectors are formatted in IBM format. The content and length of the sectors are defined by CPM. Reno
SMERESKI.WBST@XEROX.ARPA (11/20/85)
You have written a program with recursive calls. Turbo Pascal for CP/M does not generate recursive code in its default mode. You will get the expected result by including the compiler directive {$A-}. This information is in the manual. /Dave ------------------------------------------------------------------------------ I sat down to write the program for the next project I am going to give to my Computer Science I class at home on my CPM system with Turbo Pascal Version 3.00. The following program illustrates the problem with the program I wrote: program junk(input,output); procedure proca(chita:char); forward; procedure procb(chitb:char); begin writeln('Entering procb with a ',chitb); proca('A'); writeln('Leaving procb with a ',chitb); end; procedure proca; begin writeln('Entering proca with a ',chita); if chita = 'I' then procb('I'); writeln('Leaving proca with a ',chita); end; begin proca('I'); end. The output using Turbo Pascal was: Entering proca with a I Entering procb with a I Entering proca with a A Leaving proca with a A Leaving procb with a I Leaving proca with a A While the output for the same program on a VAX with BSD UNIX, IBM VM/SP CMS, or a Macintosh with MacPascal was: Entering proca with a I Entering procb with a I Entering proca with a A Leaving proca with a A Leaving procb with a I Leaving proca with a I as I expected. Calling Borland Technical Support was no help, as they wanted a copy of the program on an IBM format disk. The technical support specialist asked me to send a copy of the program on a disk. When I asked "in what format?" she replied "IBM, of course." I guess CPM does not exist anymore. Obviously, I was quite surprised at the output, and now I wonder how they tested the compiler. It seems that a program as simple as the one above should have been tested. -- Stanley Dunn University of Maryland Department of Computer Science
moews_b@h-sc1.UUCP (david moews) (11/20/85)
In article <2258@umcp-cs.UUCP> Stanley Dunn writes: > procedure proca(chita:char); forward; > procedure procb(chitb:char); > begin > writeln('Entering procb with a ',chitb); > proca('A'); > writeln('Leaving procb with a ',chitb); > end; > procedure proca; > begin > writeln('Entering proca with a ',chita); > if chita = 'I' then procb('I'); > writeln('Leaving proca with a ',chita); > end; > begin > proca('I'); > end. > The output using Turbo Pascal [under CP/M-80] was: > Entering proca with a I > Entering procb with a I > Entering proca with a A > Leaving proca with a A > Leaving procb with a I > Leaving proca with a A I don't know about Release 3.00, but in Release 2.00 of Turbo Pascal running under CP/M-80, you must compile recursive procedures and functions with the {$A-} option for them to work. Putting a {$A-} line before the line 'procedure proca(chita:char); forward;' will probably fix this problem. David Moews moews_b%h-sc1@harvard.arpa ...!harvard!h-sc1!moews_b
db21@ihuxk.UUCP (Dave Beyerl) (11/21/85)
> Replace this line with your compiler bug > > I sat down to write the program for the next project I am going > to give to my Computer Science I class at home on my CPM system > with Turbo Pascal Version 3.00. The following program illustrates > the problem with the program I wrote: > > program junk(input,output); > procedure proca(chita:char); forward; > procedure procb(chitb:char); > begin > writeln('Entering procb with a ',chitb); > proca('A'); > writeln('Leaving procb with a ',chitb); > end; > procedure proca; > begin > writeln('Entering proca with a ',chita); > if chita = 'I' then procb('I'); > writeln('Leaving proca with a ',chita); > end; > begin > proca('I'); > end. > > The output using Turbo Pascal was: > > Entering proca with a I > Entering procb with a I > Entering proca with a A > Leaving proca with a A > Leaving procb with a I > Leaving proca with a A > > While the output for the same program on a VAX with BSD UNIX, > IBM VM/SP CMS, or a Macintosh with MacPascal was: > > Entering proca with a I > Entering procb with a I > Entering proca with a A > Leaving proca with a A > Leaving procb with a I > Leaving proca with a I > > as I expected. Calling Borland Technical Support was no help, > as they wanted a copy of the program on an IBM format disk. > The technical support specialist asked me to send a copy of the > program on a disk. When I asked "in what format?" she replied > "IBM, of course." I guess CPM does not exist anymore. > > Obviously, I was quite surprised at the output, and now I > wonder how they tested the compiler. It seems that a program > as simple as the one above should have been tested. > > -- Stanley Dunn > University of Maryland Department of Computer Science Because I happened to have a copy of my Turbo Pascal compiler handy, I tried the above program in Turbo. When I ran the program, I received the second set of outputs given in the above article. The version of Turbo that I have is identified as ver. 3.01A for the IBM. Apparently, Borland either corrected this problem in the subsequent point (.01) release or there is a significant difference between the CP/M and IBM versions of Turbo. Hopes this helps in tracking down the problem. For every problem there is one Dave Beyerl solution which is simple, neat, ihuxk!db21 and wrong!
knovak@uiucme.uiucme (11/21/85)
The problem is simple!! Turbo does not default to recusion on. They do this to gain some speed. To turn on recusion use the directive {$A-} Turbo is just doing what you told it to do. Kevin J. Novak
johnson@noscvax.UUCP (Timothy A. Johnson) (11/23/85)
> Replace this line with your compiler bug > > I sat down to write the program for the next project I am going > to give to my Computer Science I class at home on my CPM system > with Turbo Pascal Version 3.00. The following program illustrates > the problem with the program I wrote: > > program junk(input,output); > procedure proca(chita:char); forward; > procedure procb(chitb:char); > begin > writeln('Entering procb with a ',chitb); > proca('A'); > writeln('Leaving procb with a ',chitb); > end; > procedure proca; > begin > writeln('Entering proca with a ',chita); > if chita = 'I' then procb('I'); > writeln('Leaving proca with a ',chita); > end; > begin > proca('I'); > end. > > The output using Turbo Pascal was: > > Entering proca with a I > Entering procb with a I > Entering proca with a A > Leaving proca with a A > Leaving procb with a I > Leaving proca with a A > > While the output for the same program on a VAX with BSD UNIX, > IBM VM/SP CMS, or a Macintosh with MacPascal was: > > Entering proca with a I > Entering procb with a I > Entering proca with a A > Leaving proca with a A > Leaving procb with a I > Leaving proca with a I > > as I expected. Calling Borland Technical Support was no help, > as they wanted a copy of the program on an IBM format disk. > The technical support specialist asked me to send a copy of the > program on a disk. When I asked "in what format?" she replied > "IBM, of course." I guess CPM does not exist anymore. > > Obviously, I was quite surprised at the output, and now I > wonder how they tested the compiler. It seems that a program > as simple as the one above should have been tested. > > -- Stanley Dunn > University of Maryland Department of Computer Science Under the PC-DOS version of Turbo 3.0, the program runs correctly with the same output as you have given for the other Pascals. The problem may be associated with the CP/M-80 Compiler Directive "A". The default is "A+" which inhibits recursive code. Switching to "A-" may solve your problem. This is documented on or about page 318 in the 3.0 manual. Timothy A. Johnson Computer Sciences Corporation