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From: grimlok@hubcap.clemson.edu (Mike Percy)
Newsgroups: comp.lang.c
Subject: Re^2: Can lint help an ANSI-C programmer?
Message-ID: <9171@hubcap.clemson.edu>
Date: 30 May 90 20:32:38 GMT
References: <6328.265D8157@puddle.fidonet.org> <1754@tkou02.enet.dec.com> <00937758.16FBE220@rigel.efd.lth.se> <24660@mimsy.umd.edu>
Organization: Clemson University, Clemson, SC
Lines: 47

cml@tove.cs.umd.edu (Christopher Lott) writes:

>Someone please correct me if some compilers flag these sorts of faults.
>gcc, for one, does not flag test-of-constant conditions, not even when
>told "-Wall -ansi -pedantic"
 
TurboC seems to do a pretty good job here with -A -wall
It catches:
ANSI Violations
  Redefinition of xxx is not identical
  Both return and return of a value used
  xxx not part od a structure
  Undefined structure xxx
  Suspicious pointer conversion
  Void functions may not return a value
  Zero length structure
Common Errors
  xxx is assigned a value that is never used
  Possible use of xxx before definition
  Code has no effect
  Parameter xxx is never used
  Possibly incorrect assignment            /* usually in  if(i = 1)...*/
  Unreachable code
  Function should return a value
Less Common Errors
  Ambigous operators need parentheses 
  Superflous & with function or array
  No declaration for function xxx
  Call to function with no prototype
  Structure passed by value           /* assuming you meant &x, not x */
  xxx declared but never used
Portability warnings
  Non-portable pointer assignment
  Constant is long
  Non-portable pointer comparison 
  Constant out of range in comparison
  Non-portable return type conversion
  Conversion may lose significant digits
  Mixing pointers to signed and unsigned char
 
These are all individually controllable also.
Incidently, I first encountered the warning about 'Conversion may lose
significant digits' dealing with a the [] operators.  I had declared p
as int far *p; and done p = (int far *p) farmalloc(100000ul); and
subsequently done something like i = foo(a,b,c); x = p[i]; and got this
warning.  The variables i and x were both properly defined.  If I
remember right, I had to decalre p as int huge *p; to make this work.