return statement check

[Nan Li]

Hello, all,
Does C/C++ ever check the return statement for a non-void function?
Look at my simple code below

int foo()
{

}

int main()
{
foo();
}

[nan@athena test]$ g++ foo.cpp
[nan@athena test]$ g++ -Wall foo.cpp
foo.cpp: In function `int foo()':
foo.cpp:4: warning: control reaches end of non-void function

There is only a warning, not an error.

Howver, in the java land, it is checked.

public class Main
{
private static int foo() {
}

public static void main( String [] args ) {
foo();
}
}

[nan@athena test]$ javac Main.java
Main.java:4: missing return statement
}
^
1 error
Is there any particular reason why C/C++ doesn't check the return
statement?

Thanks,
Nan

[lallous]

"Nan Li" <na******@gmail.com> wrote in message
news:11**********************@z14g2000cwz.googlegr oups.com...

Hello, all,
Does C/C++ ever check the return statement for a non-void function?
Look at my simple code below

int foo()
{

}

int main()
{
foo();
}

[nan@athena test]$ g++ foo.cpp
[nan@athena test]$ g++ -Wall foo.cpp
foo.cpp: In function `int foo()':
foo.cpp:4: warning: control reaches end of non-void function

There is only a warning, not an error.

Howver, in the java land, it is checked.

public class Main
{
private static int foo() {
}

public static void main( String [] args ) {
foo();
}
}

[nan@athena test]$ javac Main.java
Main.java:4: missing return statement
}
^
1 error
Is there any particular reason why C/C++ doesn't check the return
statement?

Thanks,
Nan

Hello

If you use MS VC++ 7 with its default compiler settings, it will generate an
error when not returning a value for in functions other than in main()

--
Elias

[Niels Dybdahl]

> Is there any particular reason why C/C++ doesn't check the return

statement?

Early versions of C did not have the void type...

Niels Dybdahl

[Ian]

Nan Li wrote:

Hello, all,
Does C/C++ ever check the return statement for a non-void function?
Look at my simple code below

There is no requirement to do so. The short answer as to why is that it
can't always determine if the function will return (it might go in an
endless loop, throw..).

Ian