Click and 2.4.9 kernel bug in compiling + fix

[Brecht Vermeulen]

Hi,

I had problems compiling click with linux kernel 2.4.9.

It was in the configure script, at the 
checking whether -fpermissive is required test

the answer was 'yes' because the program :
#line 3654 "configure"
#include "confdefs.h"
#define __KERNEL__
#define MODULE
#define _FEATURES_H
#define new xxx_new
#define this xxx_this
#define delete xxx_delete
#define class xxx_class
#define virtual xxx_virtual
#include <linux/skbuff.h>
int main() {
 
; return 0; }

didn't compile:
In file included from /usr/src/linux/include/linux/highmem.h:5,
                 from /usr/src/linux/include/linux/skbuff.h:27,
                 from configure:3999:
/usr/src/linux/include/asm/pgalloc.h: In function `void
flush_tlb_mm(mm_struct *)':
/usr/src/linux/include/asm/pgalloc.h:173: parse error before `::'
/usr/src/linux/include/asm/pgalloc.h: In function `void
flush_tlb_range(mm_struct *, long unsigned int, long unsigned int)':
/usr/src/linux/include/asm/pgalloc.h:187: parse error before `::'

and the next test, 'is -fpermissive allowed' did return 'no' , same
problem while compiling, so the warning was printed that the kernel
module couldn't be builded because the header files were not adapted to
C++.

I did some lookup work and arrived in include/asm/pgalloc.h 
at                
__flush_tlb();                                                                       

which is defined in pgtable.h as
#define __flush_tlb()                                                  
\
        do {                                                           
\
                unsigned int tmpreg;                                   
\
                                                                       
\
                __asm__ __volatile__(                                  
\
                        "movl %%cr3, %0;  # flush TLB \n"              
\
                        "movl %0, %%cr3;              \n"              
\
                        : "=r" (tmpreg)                                
\
                        :: "memory");                                  \
        } while (0)

to solve the problem I have changed :: in : : based on a similar thing
in the 2.2.18 patch for rwlock.h. But I don't know what this means and
if this is the correct solution (and why hasn't nobody else had this
problem before ?

best regards,
Brecht