Thread: undefined reference to `_impure_ptr'

I want to use a generic data structures library ( http://libds.sourceforge.net/ ) but when compiling, the following is displayed by GCC 3.2 on cygwin:

Code:

avltree.o(.text+0x6d7):avltree.c: undefined reference to `_impure_ptr'
avltree.o(.text+0x779):avltree.c: undefined reference to `_impure_ptr'
avltree.o(.text+0x93a):avltree.c: undefined reference to `_impure_ptr'
avltree.o(.text+0x9de):avltree.c: undefined reference to `_impure_ptr'
avltree.o(.text+0xa06):avltree.c: undefined reference to `_impure_ptr'
avltree.o(.text+0xb02):avltree.c: more undefined references to `_impure_ptr' fol
low
make[2]: [libds.a] Error 1 (ignored)

What is this _impure_ptr? Do I have to worry about it?
Thank you for your help.

>>What is this _impure_ptr?
Probably a variable used in the library.

>>Do I have to worry about it?
Since you're getting an error that is probably stopping compilation, yes, you have to worry about it.

impure_ptr is not a variable - I've checked it. It occurs in the compiled .o file but not in the source file.

I've tested it with gcc 2.95, too, and I only get four impure_ptr ... strange.

Finally, I've managed to compile the library with MSVC. No errors occured. I hope I can use the compiled library with GCC, too.