Rootcint (ing) 5.29.02, gcc "Ubuntu 4.4.3-4ubuntu5" x86_64

Hello Rooters,
I am trying to compile 5.29.02 with gcc “Ubuntu 4.4.3-4ubuntu5”, Ubuntu 10.04.2, x86_64
and get:

Generating dictionary graf3d/gl/src/G__GL.cxx...
core/utils/src/rootcint_tmp -cint -f graf3d/gl/src/G__GL.cxx -c -I/usr//include /project/etpsw/Otto.Schaile/root_lucid_x86_64/5.29.02/graf3d/gl/inc/TArc
....
#error "You need a ISO C conforming compiler to use the glibc headers"
Error: Missing one of '
\/' expected at or after line 89.
Error: Unexpected end of file (G__fgetstream():2) /usr//include/sys/cdefs.h:387:
Error: Symbol extern"C"{#define __need_size_t#define __need_NULL#include<stddef is not defined in current scope  /usr//include/stdio.h:45:
...
Error: Failed to evaluate extern"C"{#define __need_size_t#define __need_NULL#include<stddef.h>#include<bits/types
Error: Failed to evaluate extern"C"{#define __need_size_t#define __need_NULL#include<stddef.h>#include<bits/types.h>#define __need_FILE#define __need___FILE#endif#if!defined __FILE_defined&&defined __need_FILE struct _IO_FILE
Error: Symbol __BEGIN_NAMESPACE_STD typedef struct _IO_FILE FILE is not defined in current scope  /usr//include/stdio.h:49:
Error: Missing one of '{' expected at or after line 91.
...

Anybody knows, what I do wrongly?
Previously I happily compiled 5.28.00b etc.

Cheers,
Otto

with help from Fons I found the problem:
I had for historical reason a:

in my .bashrc
This made it via configure and the variable OPENGLINCDIR
into the argument list of rootcint rootcint ... -I/usr//include ...
where it never should be.
(To be more precise: because of the extra / it was not filtered out.)

so mea culpa
Otto