Re: why are missing return statements from non-void functions not a

From:

=?ISO-8859-1?Q?Daniel_Kr=FCgler?= <daniel.kruegler@googlemail.com>

Newsgroups:

comp.lang.c++.moderated

Date:

Thu, 29 Jul 2010 13:01:43 CST

Message-ID:

<e9a04e36-532c-4f6e-ae6a-461470c2d48d@q35g2000yqn.googlegroups.com>

On 29 Jul., 17:05, Goran Pusic <gor...@cse-semaphore.com> wrote:

Also, note that at the call site, you are not required to use return
value, so ultimately e.g. this:

int f(int g)
{
if (g==5)
  return 7;
// and else?
}

int main(int, const char*[])
{
  int i = f(5);
  f(6); // don't care about result, nor is there one, too!
}

will work.

Sorry, this is nonsense. The above code produces undefined
behavior, see 6.6.3/2:

"Flowing off the end of a function is equivalent to a return with
no value; this results in undefined behavior in a value-returning
function."

Which is not to say that it's a good idea, but hey... Would you say
that even K&R knew what would a good idea be when they wrote first C
(same goes for many-a-language author)? For example, K&R thought
worthwhile putting

void strcpy(char* dest, const char* src)
{
while (*dest++ = *src++);
}

into their C book, but he who wrote this today would probably be
called code red on in a code review. ;-)

I don't see anything wrong with that code.

Greetings from Bremen,

Daniel Kr?gler

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