From:	"Thomas Harte" <T DOT Harte AT btinternet DOT _c_o_m_>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Warning : if (x=y)
Date:	Sat, 9 Sep 2000 13:05:25 +0100
Organization:	BT Internet
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Rafał Maj wrote in message <8pd7q6$ljs$2 AT info DOT cyf-kr DOT edu DOT pl>...
>What is command-line option for turning on warning messages for this
>expression ?


I don't think there is one, since it is perfectly valid syntax. It assigns
the value of x to y, and then evaluates the if statement based on that
value - 'TRUE' if the value is non-zero. In actual fact these assignments
are terribly useful, for example :

char *a;

if (a = (char *)malloc(32)) //with (char *) cast for pedants / C++ users
{
 ...
}
else
  printf("Malloc failed");

If the malloc succeeds, 'a' correctly points to the 32 bytes of memory.

-Thomas

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