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digitalmars.D.bugs - return type of main (should be int or void)

Some test programs (one-liners):


 void main() {}


$ dmd main1.d

 void main(char[][] args) {}


$ dmd main2.d

 void main(char[] string) {}


$ dmd main3.d
main3.d:1: function main3.main parameters must be main() or 
main(char[][] args)

So far, so good. But then comes:


 int main() { return 0; }


$ dmd main4.d

 int main(char[][] args) { return 0; }


$ dmd main5.d

 char[] main() { return "EXIT_SUCCESS"; }


$ dmd main6.d

i.e. No errors (on Mac OS X), until you run it:


 $ ./main6; echo $?
 Bus error


similar on Linux, when using the GDC compiler:


 $ ./main6; echo $?
 Segmentation fault


but, if you compile it on Linux X86: (with DMD)


 $ ./main6; echo $?
 12



I think that main should be *forced* to return int or void,
where "void" would mean that the program would return a 0...


This would shorten small programs,

from:

 int main()
 {
     printf("Hello, World!\n");
     return 0;
 }


to:

 import std.stdio;
 void main()
 {
     writefln("Hello, World!");
 }


At least some constants from C's /usr/include/stdlib.h
could be used, to make D programs more self-documenting:


 import std.stdio;
 import std.c.stdlib;
 int main()
 {
     writefln("Hello, World!");
     return EXIT_SUCCESS;
 }



In summary, "void main()" should be either defined or invalid
- to avoid this: http://users.aber.ac.uk/auj/voidmain.shtml ?

Currently it has different results for DMD and GDC compilers....

--anders

PS.
"12" was of course (?) the length of the string "EXIT_SUCCESS"
See my previous post, currently DMD returns register EAX (!):
http://www.digitalmars.com/drn-bin/wwwnews?digitalmars.D/13127
Jan 12 2005