Arch Linux

Description:
it is strange. so hard to describe it. given the steps:
1 touch a new file, a.cpp
2 $vim a.cpp
3 paste the code below:
====CODE======
int main() {
a[2][2]={
{7, 6}};
return 0;
}
====CODE======
you must type it strictly, line feeds and spaces.
4 save it
5 go to line 3 (contains {7, 6}), and type `o'.
6 ok, it is hanged now.

about the code.
====CODE======
int main() { // here must be a left brace
a[2][2]={ // squal sign and left brace
{7, 6}}; // some spaces (one or two or more), then form as the input (the comma the the space after the comma and a right brace).
return 0; // not necessary
} // right brace
====CODE======

Additional info:
* package version(s)
gvim 7.3.353-2
vim-runtime 7.3.353-2

* config and/or log files etc.
It is not related to the vimrc file. The file is renamed, and this is still happened.