I've never trusted common variables. Take those bare ints out of

latin.h and put them in latin.c with 'extern' declarations in the
header.

[originally from svn r8794]

latin.c

@@ -16,6 +16,10 @@
  * Solver.
  */
 
+#ifdef STANDALONE_SOLVER
+int solver_show_working, solver_recurse_depth;
+#endif
+
 /*
  * Function called when we are certain that a particular square has
  * a particular number in it. The y-coordinate passed in here is

latin.h

@@ -8,7 +8,7 @@ typedef unsigned char digit;
 /* --- Solver structures, definitions --- */
 
 #ifdef STANDALONE_SOLVER
-int solver_show_working, solver_recurse_depth;
+extern int solver_show_working, solver_recurse_depth;
 #endif
 
 struct latin_solver {