Linker and Libraries Guide

Fatal Resolutions

Symbol conflicts that cannot be resolved result in a fatal error condition and an appropriate error message. This message indicates the symbol name together with the names of the files that provided the symbols. No output file is generated. Although the fatal condition is sufficient to terminate the link-edit, all input file processing is first completed. In this manner, all fatal resolution errors can be identified.

The most common fatal error condition exists when two relocatable objects both define non-weak symbols of the same name.


$ cat foo.c
int bar = 1;

$ cat bar.c
int bar()
{ 
        return (0);
}

$ ld -r -o temp.o foo.c bar.c
ld: fatal: symbol `bar' is multiply-defined:
        (file foo.o and file bar.o);
ld: fatal: File processing errors. No output written to int.o

foo.c and bar.c have conflicting definitions for the symbol bar. Because the link-editor cannot determine which should dominate, the link-edit usually terminates with an error message. You can use the link-editor's -z muldefs option to suppress this error condition. This option allows the first symbol definition to be taken.