[date-utilities] avoid report crash if start>end date

libgnucash/app-utils/date-utilities.scm

@@ -339,6 +339,11 @@
     (assv-ref MonthDeltas incr))
   (define (make-interval from to)
     (list from (if (< to enddate) (decdate to SecDelta) enddate)))
+  (when (< enddate startdate)
+    (let ((saved-enddate enddate))
+      (gnc:warn "start > end date. Swapping dates to avoid some reports crashing.")
+      (set! enddate startdate)
+      (set! startdate saved-enddate)))
   (let loop ((result '())
              (date startdate)
              (idx 0))
@@ -365,6 +370,11 @@
 (define (gnc:make-date-list startdate enddate incr)
   (define month-delta
     (assv-ref MonthDeltas incr))
+  (when (< enddate startdate)
+    (let ((saved-enddate enddate))
+      (gnc:warn "start > end date. Swapping dates to avoid some reports crashing.")
+      (set! enddate startdate)
+      (set! startdate saved-enddate)))
   (let loop ((result '())
              (date startdate)
              (idx 0))