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1987-06-18
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*****
The following bugs were listed by Gene Alm on 14 June 1987.
As of this writing, they have NOT been reported to Frank
Borland by the reporter. They will be reported within a day
or two.
***
Error Class: Error in math.h
In the header file math.h, you will find:
#define M_PI 3.14159265358979224
This should read:
#define M_PI 3.14159265358979324
Reference: Don Knuth, Seminumerical Algorithms
Comments: I have not checked any other values. Are
there any other dumb errors in these
constants???
Disposition: Unreported
***
Error Class: Documentation error
On page 144 of the Users Guide, there is an error in
the syntax shown for enumerated variables. It reads:
enum days = { Sun, Mon, Tues, Wed,
Thurs, Fri, Sat };
It should read:
enum days { Sun, Mon, Tues, Wed,
Thurs, Fri, Sat };
Reference: Lattice C Compiler Version 3.00 Technical
Bulletin
Comments: The enum data type is quite a bit more flexible
than implied in the illustration given. Consult
a good reference.
Disposition: Unreported
***
Error Class: Documentation error
On page 297 of the Reference Guide, it states that the
-nxxx environment option sends the .OBJ and .ASM files
to the directory or path given in xxx.
It ALSO sends load modules (.EXE) files to this path.
Reference: Try it and see!
Comments: I like to send temporary files (I usually
consider .OBJ files as temporaries) to a ramdisk
for speed but like to keep load modules on the
current drive (hard disk). The command line
options by themselves don't seem to support
sending .OBJ and .EXE files to different drives
(paths).
Disposition: Unreported
***
Error Class: Documentation error
On page 18 of the Reference Guide, the usage for _fmode
is shown as:
extern int _fmode;
If you look in the fcntl.h header file, you will discover
that the declaration is:
extern unsigned _Cdecl _fmode;
This confusion between an integer and an unsigned may
manifest itself in a warning message during compilation.
Reference: See for yourself!
Comments: This is a common nuisance for a new product.
The documentation doesn't agree with the facts.
So assume the facts are correct. Go with the
declaration as shown in the header file since
it is PROBABLY more current than the manual.
Disposition: Unreported
***
Error class: Compiler error
If the following code is compiled, the compiler will return
a message that "code in line 9 has no effect." Well
that is not true since if you execute the program the results
that are listed via the two printf statements are different.
The code does indeed have an effect. Fortunately the compiler
ignores its own warning and generates the correct code for a
statement that it says is redundant. The statement is
syntactically correct. The leading asterisk indicates a
dereferencing that is not used and this appears to be the
problem that the compiler recoginzes. Removing this asterisk
causes the message to disappear. But in C, I am allowed to
do what I want to do even if it makes no sense! The compiler
should issue a redundant operator message, not a redundant
code message!
static int a[] = {0, 1, 2, 3, 4};
static int *p[] = {a, a+1, a+2, a+3, a+4};
static int **pp;
void main () {
pp = p;
printf ("\n%10d%10d%10d", pp-p, *pp-a, **pp);
*++*pp;
printf ("\n%10d%10d%10d", pp-p, *pp-a, **pp);
}
Reference: Kernighan and Ritchie
Comments: When receiving a message such as "code is
bad", just how much of it is bad? If the compiler
recognizes redundant operators or statements,
it might well inform the programmer of the "find".
Other compilers don't inform the user that a
redundant construct has been used. I am delighted
that this environment tells me about it. More
often than not, such a message will indicate that
there is a problem. But don't simply say that code
is bad.
Disposition: Unreported
***
Documentation error
On page 78 of the Reference Guide, the usage for
farcoreleft is given as:
long farcoreleft (void);
In the alloc.h header file, the prototype is shown as:
unsigned long _Cdecl farcoreleft(void);
Reference: See for yourself
Comments: Once again, if the documentation differs from
the information given in a header file, assume
that the header file contains the latest, and
therefore the most correct information.
Disposition: Unreported
***
Error class: Compiler error
When the following program is executed, you will get
two different results. Casting values in the expression
for xr0 does not alter the situation.
#define MAX_POINTS 16
main () {
int points, index;
double xr0, xr1;
points = MAX_POINTS;
for (index = 0; index < points; index++) {
xr0 = 512.0 / MAX_POINTS * index;
xr1 = 512 / MAX_POINTS * index;
printf ("\n%20.6lf%20.6lf", xr0, xr1);
}
}
Reference: Kernighan and Ritchie
Comments: If the order of the terms in xr0 is changed
(xr0 = 512.0 * index / MAX_POINTS), the results
will change. Since the order of the terms should
make no difference, this is a serious bug. Other
compilers handle the above code with no problem.
It appears as though the compiler doesn't like
the appearance of two constants together. If
you suspect this problem, interchange the order
of the terms.
Disposition: Unreported
***
******************************************************************
16 June 1987
There are a plethora of bugs in the documentation relating
to the agreement between the RG (Reference Guide) and the
header files. I looked at these and here are some of the
problems that I found. Only the disagreements are stated:
the correct prototype (in some cases) is not clear.
******************************************************************
Page 15 of RG
It says that extern char *sys_errlist [];
and extern int sys_nerr;
are in errno.h. They are in stdlib.h, not errno.h.
Page 19 of RG
It says that extern unsigned int _psp;
is in stdlib.h. It is in dos.h, not stdlib.h.
Page 27 of RG
The prototype for setblock is shown as
int setblock (int set, int newsize);
It is shown in dos.h as
int _Cdecl setblock(unsigned segx, unsigned newsize);
Page 45 of RG
The prototype for brk is shown as
int brk (void *endds);
It is shown in alloc.h as
int _Cdecl brk(char *addr);
The prototype for sbrk is shown as
char *sbrk (int incr);
It is shown in alloc.h as
void *_Cdecl sbrk(int incr);
Page 46 of RG
The prototype for bsearch is shown as
void *bsearch (void *key, void *base, int *nelem,
int width, int (*fcmp)());
It is shown in stdlib.h as
void *_Cdecl bsearch(void *key, void *base, int nelem,
int width, int _Cdecl (*fcmp)());
The prototype for lfind is shown as
void *lfind (void *key, void *base, int *nelem,
int width, int (*fcmp)());
It is shown in stdlib.h as
void *_Cdecl lfind (void *key, void *base, unsigned *num,
int width, int _Cdecl (*fcmp)());
The prototype for lsearch is shown as
void *lsearch (void *key, void *base, int *nelem,
int width, int (*fcmp)());
It is shown in stdlib.h as
void *_Cdecl lsearch(void *key, void *base, unsigned *num,
int width, int _Cdecl (*fcmp)());
Page 70 of RG
The prototype for eof is shown as
int eof (int *handle);
It is shown in io.h as
int _Cdecl eof(int handle);
Page 78 of RG
The prototype for farcoreleft is shown as
long farcoreleft (void);
It is shown in alloc.h as
unsigned long _Cdecl farcoreleft(void);
Page 101 of RG
The prototype for fread is shown as
int fread (void *ptr, int size, int nitems, FILE *stream);
It is shown in stdio.h as
int _Cdecl fread (void *ptr, unsigned size, unsigned n, FILE *fp);
The prototype for fwrite is shown as
int fwrite (void *ptr, int size, int nitems, FILE *stream);
It is shown in stdio.h as
int _Cdecl fwrite(void *ptr, unsigned size, unsigned n, FILE *fp);
Page 105 of RG
The prototype for fstat is shown as
int fstat (char *handle, struct stat *buff)
It is shown in stat.h as
int fstat (int fildes, struct stat *statbuf);
Page 106 of RG
The prototype for fwrite is discussed above with Page 101
of RG.
It says that when using gcvt you should use the statement
#include <dos.h>
It should say that you should use the statement
#include <stdlib.h>
Page 107 of RG
The prototype for ungetch is shown as
int ungetch (int c);
It is shown in conio.h as
int _Cdecl ungetch(unsigned ch);
Page 114 of RG
The prototype for getdfree is shown as
void getdfree (int drive, struct dfree *dfreep);
It is shown in dos.h as
int _Cdecl getdfree(unsigned char drive, struct dfree *dtable);
Page 117 of RG
The prototype for getfat is shown as
void getfat (int drive, struct fatinfo *fatblkp);
It is shown in dos.h as
int _Cdecl getfat(unsigned char drive, struct fatinfo *dtable);
The prototype for getfatd is shown as
void getfatd (struct fatinfo *fatblkp);
It is shown in dos.h as
int _Cdecl getfatd(struct fatinfo *dtable);
Page 118 of RG
The prototype for getftime is in io.h and not in dos.h
as indicated.
Page 123 of RG
The prototype for setverify is shown as
void setverify (int value);
It is shown in dos.h as
int _Cdecl setverify(int value);
Page 125 of RG
The prototype for hardretn is shown as
void hardretn (int errcode);
It is shown in dos.h as
int _Cdecl hardretn(int retn);
Page 128 of RG
The prototype for hardretn is discussed with page 125 of RG.
Page 136 of RG
The prototype for ioctl is shown as
int ioctl (int handle, int cmd [, int *argdx, int argcx]);
It is shown in io.h as
int _Cdecl ioctl(int handle, char func, ...);
/* optional 3rd and 4th args are: void * argdx, int argcx */
Page 138 of RG
The prototypes for is... are to be found in ctype.h, not
in io.h as stated.
Page 141 of RG
The prototype for keep is shown as
void keep (int status, int size);
It is shown in dos.h as
void _Cdecl keep(unsigned char status, unsigned size);
Page 142 of RG
The prototype for lfind is shown as
void *lfind (void *key, void *base, int *nelem
int width, int (*fcmp)());
It is shown in stdlib.h as
void *_Cdecl lfind (void *key, void *base, unsigned *num,
int width, int _Cdecl (*fcmp)());
Page 146 of RG
The discussion of lsearch is to be found with page 46
comments.
The prototype for lseek is shown as
long lseek (int handle, long offset, int fromwhere);
It is shown in io.h as
long _Cdecl lseek(int handle, long offset, unsigned char kind);
Page 154 of RG
The prototype for memchr is shown as
void *memchr (void *s, char ch, unsigned n);
It is shown in mem.h as
void *_Cdecl memchr(void *s, unsigned char c, unsigned n);
The prototype for memcmp is shown as
void *memcmp (void *s1, void *s2, unsigned n);
It is shown in mem.h as
int _Cdecl memcmp(void *s1, void *s2, unsigned n);
The prototype for memset is shown as
void *memset (void *s, char ch, unsigned n);
It is shown in mem.h as
void *_Cdecl memccpy(void *dest, void *src, unsigned char c,
unsigned n);
Page 156 of RG
MK_FP is implemented as a macro as shown in dos.h. The
description for MK_FP given in the RG should note this.
Page 158 of RG
The prototype for movedata is shown as
void movedata (int segsrc, int offsrc, int segdest,
int offdest, unsigned numbytes);
It is shown in mem.h as
void _Cdecl movedata(unsigned srcseg, unsigned srcoff,
unsigned dstseg, unsigned dstoff, unsigned n);
Page 159 of RG
The prototype for setmem is shown as
void setmem (void *addr, int len, char value);
It is shown in mem.h as
void _Cdecl setmem(void *dest, unsigned length, char value);
Page 160 of RG
The prototype for _open is shown as
int _open (char *pathname, int access);
It is shown in io.h as
int _Cdecl _open (char *filename, unsigned oflags);
The prototype for open is shown as
int open (char *pathname, int access [, int permiss]);
It is shown in io.h as
int _Cdecl open(char *path, unsigned access,...
/*unsigned mode*/);
For both of the above functions, be sure to #include <io.h>
to access the prototypes.
Page 163 of RG
The prototype for parsfnm is shown as
char *parsfnm (char *cmdline, struct fcb *fcbptr,
int option);
It is shown in dos.h as
char *_Cdecl parsfnm(char *cmdline, struct fcb *fcb,
unsigned char opt);
Page 164 of RG
The prototype for peek is shown as
char peek (int segment, unsigned offset);
It is shown in dos.h as
int _Cdecl peek(unsigned segment, unsigned offset);
The prototype for peekb is shown as
char peekb (int segment, unsigned offset);
It is shown in dos.h as
int _Cdecl peekb(unsigned segment, unsigned offset);
Page 166 of RG
The prototype for poke is shown as
void poke (int segment, int offset, int value);
It is shown in dos.h as
void _Cdecl poke(unsigned segment, unsigned offset, int value);
The prototype for pokeb is shown as
void pokeb (int segment, int offset, char value);
It is shown in dos.h as
void _Cdecl pokeb(unsigned segment, unsigned offset, char value);
Page 168 of RG
The cprintf function will be found in conio.h and not
in stdio.h.
Page 181 of RG
The prototype for fputc is shown as
int fputc (int ch, FILE *stream);
It is shown in stdio.h as
int _Cdecl fputc (char c, FILE *fp);
The putch function will be found in conio.h and not
in stdio.h.
The prototype for putw is shown as
int putw (int w, FILE *stream);
It is shown in stdio.h as
int _Cdecl putw (unsigned w, FILE *fp);
Page 184 of RG
The putw function is discusssed in the page 181 information.
Page 185 of RG
The prototype for qsort is shown as
void qsort (void *base, int nelem, int width,
int (*fcmp)());
It is shown in stdlib.h as
void _Cdecl qsort (void *base,
unsigned nelem,
unsigned width,
int _Cdecl (*fcmp)());
Page 188 of RG
The prototype for read is shown as
int read (int handle, void *buf, int nbyte);
It is shown in io.h as
int _Cdecl read (int handle, char *buf, unsigned int len);
Page 190 of RG
The prototype for rewind is shown as
int rewind (FILE *stream);
It is shown in stdio.h as
void _Cdecl rewind (FILE *fp);
Page 191 of RG
The discussion of sbrk is shown with that for page 45.
The cscanf prototype is found in conio.h and not in
stdio.h.
Page 205 of RG
The discussion of setblock is shown with that for page 27.
The prototype for setbuf is shown as
void setbuf (FILE *stream, char *buf);
It is shown in io.h as
void _Cdecl setbuf (FILE *fp, void *buf);
The prototype for setvbuf is shown as
int setvbuf (FILE *stream, char *buf, int type,
unsigned size);
It is shown in io.h as
int _Cdecl setvbuf (FILE *stream, void *buf, int type,
unsigned size);
Page 209 of RG
The discussion of setmem is shown with that for page 159.
Page 210 of RG
The prototype for setmode is shown as
int setmode (int handle, unsigned mode);
It is shown in io.h as
int _Cdecl setmode (int handle, int amode);
Page 211 of RG
The discussion of setvbuf is shown with that for page 205.
The discussion of setverify is shown with that for page 123.
Page 212 of RG
The prototype for sleep is shown as
unsigned sleep (unsigned seconds);
It is shown in dos.h as
void _Cdecl sleep(unsigned seconds);
Page 221 of RG
The discussion of fstat is shown with that for page 105.
Page 224 of RG
The prototype for strcspn is shown as
int strcspn (char *str1, char *str2);
It is shown in string.h as
size_t _Cdecl strcspn(char *s1, char *s2);
The type size_t is typedef'd to be other than int.
The prototype for strncat is shown as
char *strncat (char *destin, char *source, int maxlen);
It is shown in string.h as
char *_Cdecl strncat(char *dest, char *src, unsigned maxlen);
The prototype for strncmp is shown as
int strncmp (char *str1, char *str2, int maxlen);
It is shown in string.h as
int _Cdecl strncmp(char *s1, char *s2, unsigned maxlen);
The prototype for strncpy is shown as
char *strncpy (char *destin, char *source, int maxlen);
It is shown in string.h as
char *_Cdecl strncpy(char *dest, char *src, unsigned maxlen);
The prototype for strspn is shown as
int strspn (char *str1, char *str2);
It is shown in string.h as
size_t _Cdecl strspn(char *s1, char *s2);
The prototypes for strtod and strtol were not to be found
in the appropriate header files (stdlib.h and string.h).
Page 234 of RG
The prototype for swab is shown as
void swab (char *from, char *to, int nbytes);
It is shown in stdlib.h as
void _Cdecl swab (void *from, void *to, unsigned nbytes);
Page 241 of RG
The prototype for ungetc is shown as
int ungetc (char c, FILE *stream);
It is shown in stdio.h as
int _Cdecl ungetc (int c, FILE *fp);
Page 243 of RG
The prototype for unlock is given in io.h and not in
dos.h as shown.
Page 249 of RG
The prototype for write is shown as
int write (int handle, void *buf, int nbyte);
It is shown in io.h as
int _Cdecl write (int handle, char *buf, unsigned int len);
