I have retried under Ubuntu and CRUX Linux. Same output:

root@toshiba:~# gcc 7_2.c
root@toshiba:~# ./a.out

//blinking cursor ( 10 - 15 mins then termination )
Which OS are you using? Wait, I'll try under GCC 3.

root@toshiba:~# gcc -v
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v --enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr --enable-shared --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.1.3 --program-suffix=-4.1 --enable-__cxa_atexit --enable-clocale=gnu --enable-libstdcxx-debug --enable-mpfr --enable-checking=release i486-linux-gnu
Thread model: posix
gcc version 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)
I am stuck at this point of arrays for the programs I write complain the same.