Added a new "--force-import" command line option to the linker.

git-svn-id: svn://svn.cc65.org/cc65/trunk@4052 b7a2c559-68d2-44c3-8de9-860c34a00d81

doc/ld65.sgml

@@ -77,6 +77,7 @@ Long options:
   --define sym=val      Define a symbol
   --dump-config name    Dump a builtin configuration
   --end-group           End a library group
+  --force-import sym    Force an import of symbol `sym'
   --help                Help (this text)
   --lib file            Link this library
   --lib-path path       Specify a library search path
@@ -263,6 +264,22 @@ Here is a description of all the command line options:
   file and it's contents are subject to change without further notice.
 
 
+  <tag><tt>--force-import sym[:addrsize]</tt></tag>
+
+  Force an import of a symbol. While object files are always linked to the
+  output file, regardless if there are any references, object modules from
+  libraries get only linked in if an import can be satisfied by this module.
+  The <tt/--fore-import/ option may be used to add a reference to a symbol and
+  as a result force linkage of the module that exports the identifier.
+
+  The name of the symbol may be followed by a colon and an address size
+  specifier. If no address size is specified, the default address size
+  for the target machine is used.
+
+  Please note that the symbol name needs to have the internal representation,
+  meaning you have to prepend an underline for C identifiers.
+
+
   <tag><tt>--lib file</tt></tag>
 
   Links a library to the output. Use this command line option instead of just