caller_locations-with-columns.patch

$ d
diff --git a/vm_backtrace.c b/vm_backtrace.c
index bb01983a7c..de7b961174 100644
--- a/vm_backtrace.c
+++ b/vm_backtrace.c
@@ -47,6 +47,28 @@ calc_lineno(const rb_iseq_t *iseq, const VALUE *pc)
     return rb_iseq_line_no(iseq, pos);
 }

+inline static int
+calc_column(const rb_iseq_t *iseq, const VALUE *pc)
+{
+    size_t pos = (size_t)(pc - iseq->body->iseq_encoded);
+    if (LIKELY(pos)) {
+        /* use pos-1 because PC points next instruction at the beginning of instruction */
+        pos--;
+    }
+#if VMDEBUG && defined(HAVE_BUILTIN___BUILTIN_TRAP)
+    else {
+        /* SDR() is not possible; that causes infinite loop. */
+        rb_print_backtrace();
+        __builtin_trap();
+    }
+#endif
+    int beg_pos_lineno, beg_pos_column, end_pos_lineno, end_pos_column;
+    const rb_code_location_t *loc = &iseq->body->location.code_location;
+    printf("\n(%d, %d, %d, %d)\n", loc->beg_pos.lineno, loc->beg_pos.column, loc->end_pos.lineno, loc->end_pos.column);
+    rb_iseq_code_location(iseq, &beg_pos_lineno, &beg_pos_column, &end_pos_lineno, &end_pos_column);
+    return beg_pos_lineno;
+}
+
 int
 rb_vm_get_sourceline(const rb_control_frame_t *cfp)
 {
@@ -80,6 +102,10 @@ typedef struct rb_backtrace_location_struct {
 		const VALUE *pc;
 		int lineno;
 	    } lineno;
+	    union {
+		const VALUE *pc;
+		int column;
+	    } column;
 	} iseq;
 	struct {
 	    ID mid;
@@ -156,6 +182,27 @@ location_lineno(rb_backtrace_location_t *loc)
     }
 }

+static int
+location_column(rb_backtrace_location_t *loc)
+{
+    switch (loc->type) {
+      case LOCATION_TYPE_ISEQ:
+	loc->type = LOCATION_TYPE_ISEQ_CALCED;
+	return (loc->body.iseq.column.column = calc_column(loc->body.iseq.iseq, loc->body.iseq.column.pc));
+      case LOCATION_TYPE_ISEQ_CALCED:
+	return loc->body.iseq.column.column;
+      case LOCATION_TYPE_CFUNC:
+	if (loc->body.cfunc.prev_loc) {
+	    return location_column(loc->body.cfunc.prev_loc);
+	}
+	return 0;
+      default:
+	rb_bug("location_column: unreachable");
+	UNREACHABLE;
+    }
+}
+
+
 /*
  * Returns the line number of this frame.
  *
@@ -170,6 +217,20 @@ location_lineno_m(VALUE self)
     return INT2FIX(location_lineno(location_ptr(self)));
 }

+/*
+ * Returns the column number of this frame.
+ *
+ * For example, using +caller_locations.rb+ from Thread::Backtrace::Location
+ *
+ *	loc = c(0..1).first
+ *	loc.column #=> 2
+ */
+static VALUE
+location_column_m(VALUE self)
+{
+    return INT2FIX(location_column(location_ptr(self)));
+}
+
 static VALUE
 location_label(rb_backtrace_location_t *loc)
 {
@@ -517,6 +578,7 @@ bt_iter_iseq(void *ptr, const rb_control_frame_t *cfp)
     loc->type = LOCATION_TYPE_ISEQ;
     loc->body.iseq.iseq = iseq;
     loc->body.iseq.lineno.pc = pc;
+    loc->body.iseq.column.pc = pc;
     arg->prev_loc = loc;
 }

@@ -1078,6 +1140,7 @@ Init_vm_backtrace(void)
     rb_undef_alloc_func(rb_cBacktraceLocation);
     rb_undef_method(CLASS_OF(rb_cBacktraceLocation), "new");
     rb_define_method(rb_cBacktraceLocation, "lineno", location_lineno_m, 0);
+    rb_define_method(rb_cBacktraceLocation, "column", location_column_m, 0);
     rb_define_method(rb_cBacktraceLocation, "label", location_label_m, 0);
     rb_define_method(rb_cBacktraceLocation, "base_label", location_base_label_m, 0);
     rb_define_method(rb_cBacktraceLocation, "path", location_path_m, 0);