what i want:

If you want to use the omnicompletion or omnicompletion function in vim to realize automatic completion of glibc functions, for example, enter pri in the C source file, and then press C-x C-o to pop up the list to complete printf, and so on.
The problem now is that I use ctags to process the standard C header files installed by glibc-headers-2.15-57.fc17.i686 and generate the tags_glibc file. But enter pri in the C source file, and then C-x C-o. In the pop-up menu, there are only the definition and prototype declaration of printf in stdio2.h, but not the printf declaration of stdio.h. What is strange is that I used vim to view the generated tags file, searched for printf, and found the following three entries:

printf	/usr/include/bits/stdio2.h	/^printf (__const char *__restrict __fmt, ...)$/;"	f
printf	/usr/include/bits/stdio2.h	108;"	d
printf	/usr/include/stdio.h	/^extern int printf (__const char *__restrict __format, ...);$/;"	p

The last one shows that ctags does generate the prototype declaration (type p) of printf in stdio.h, but why can’t I see the third one when I enter pri<C-x C-o> in insert mode? Where did I go wrong? ?
The same phenomenon also occurs in functions such as fprintf (this symbol is available in stdio.h and stdio2.h), memcpy (available in string.h and string3.h).

environment

My system is fedora17 (3.6.3-1.fc17.i686), ctags is the latest version, 5.8
The ctags command used is as follows:

ctags --langmap=c:.c.h --language-force=c -h .h --c-kinds=+pxl  --exclude='tags*' --exclude='*swp' --exclude='*~' --exclude='*[!ch]' -I _THROW -I __attribute__+ -I __wur -f tags_glibc -L glibc-headers-filelist.txt 

Among them, the generation of glibc-headers-filelist.txt is the following command:

rpm -ql glibc-headers |grep '\.h' >glibc-headers-filelist.txt

question

Dear vim experts, is there any way to better generate the tags file of the glibc header file