typo in fold-const.c prevents GCC 2.3.1 from catching some overflows

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1 total messages Started by Paul Eggert Mon, 02 Nov 1992 23:54

#49

Author: Paul Eggert
Date: Mon, 02 Nov 1992 23:54

36 lines
1850 bytes

GCC 2.3.1 (sparc, SunOS 4.1.2) doesn't warn about the integer overflow
in the program:

	long long x = 9223372036854775807LL + 1;

due to a parenthesization typo (of mine, sorry!) in fold-const.c.
Here is a patch.

Mon Nov  2 23:51:14 1992  Paul Eggert  (eggert@twinsun.com)

	* fold-const.c (same_sign): Fix parenthesization typo.

===================================================================
RCS file: fold-const.c,v
retrieving revision 2.3
retrieving revision 2.3.1.1
diff -c -r2.3 -r2.3.1.1
*** fold-const.c	1992/10/21 21:14:52	2.3
--- fold-const.c	1992/11/02 23:51:14	2.3.1.1
***************
*** 62,68 ****
  #define left_shift_overflows(a, b)  ((a)  !=  ((a) << (b)) >> (b))
  
  /* Yield nonzero if A and B have the same sign.  */
! #define same_sign(a, b) ((a) ^ (b) >= 0)
  
  /* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow.
     Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1.
--- 62,68 ----
  #define left_shift_overflows(a, b)  ((a)  !=  ((a) << (b)) >> (b))
  
  /* Yield nonzero if A and B have the same sign.  */
! #define same_sign(a, b) (((a) ^ (b)) >= 0)
  
  /* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow.
     Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1.

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