gdb:

* configure.ac (--with-relocated-sources): New.
	* configure, config.in: Regenerate.
	* source.c (add_substitute_path_rule): Remove static.
	* source.h (add_substitute_path_rule): Declare.
	* main.c: Include "source.h".
	(captured_main): Add substitution rule if RELOC_SRCDIR.

gdb/doc:
	* gdb.texinfo (Source Path): Document --with-relocated-sources.

gdb/main.c

@@ -40,6 +40,8 @@
 #include "interps.h"
 #include "main.h"
 
+#include "source.h"
+
 /* If nonzero, display time usage both at startup and for each command.  */
 
 int display_time;
@@ -359,6 +361,12 @@ captured_main (void *data)
 
   get_init_files (&system_gdbinit, &home_gdbinit, &local_gdbinit);
 
+#ifdef RELOC_SRCDIR
+  add_substitute_path_rule (RELOC_SRCDIR,
+			    make_relative_prefix (argv[0], BINDIR,
+						  RELOC_SRCDIR));
+#endif
+
   /* There will always be an interpreter.  Either the one passed into
      this captured main, or one specified by the user at start up, or
      the console.  Initialize the interpreter to the one requested by