diff --git a/src/cpp/solve.cpp b/src/cpp/solve.cpp
index 38490f23..084664a5 100644
--- a/src/cpp/solve.cpp
+++ b/src/cpp/solve.cpp
@@ -69,67 +69,65 @@ int solveworker::possibsolution(const puzdef &pd, int sp) {
 int solveworker::solveiter(const puzdef &pd, prunetable &pt, int togo, int sp, int st) {
    int v, mi, m ;
    ull mask, skipbase ;
-top:
-   lookups++ ; 
-   v = pt.lookup(posns[sp], looktmp) ;
-   if (v > togo + 1) {
-      v = -1 ;
-   } else if (v > togo) {
-      v = 0 ;
-   } else if (v == 0 && togo == 1 && didprepass && pd.comparepos(posns[sp], pd.solved) == 0) {
-      v = 0 ;
-   } else if (v == 0 && togo > 0 && noearlysolutions && pd.comparepos(posns[sp], pd.solved) == 0) {
-      v = 0 ;
-   } else if (togo == 0) {
-      v = possibsolution(pd, sp) ;
-   } else {
-      mask = canonmask[st] ;
-      skipbase = 0 ;
-      mi = -1 ;
-      goto topm ;
-   }
-returnval:
-   if (solvestates.size() == 0)
-      return v ;
-   {
-      auto &ss = solvestates[solvestates.size()-1] ;
-      togo++ ;
-      sp-- ;
-      st = ss.st ;
-      mi = ss.mi ;
-      mask = ss.mask ;
-      skipbase = ss.skipbase ;
-   }
-   solvestates.pop_back() ;
-   if (v == 1)
-      goto returnval ;
-   if (!quarter && v == -1) {
+   while (1) {
+      lookups++ ; 
+      v = pt.lookup(posns[sp], looktmp) ;
+      if (v > togo + 1) {
+         v = -1 ;
+      } else if (v > togo) {
+         v = 0 ;
+      } else if (v == 0 && togo == 1 && didprepass && pd.comparepos(posns[sp], pd.solved) == 0) {
+         v = 0 ;
+      } else if (v == 0 && togo > 0 && noearlysolutions && pd.comparepos(posns[sp], pd.solved) == 0) {
+         v = 0 ;
+      } else if (togo == 0) {
+         v = possibsolution(pd, sp) ;
+      } else {
+         mask = canonmask[st] ;
+         skipbase = 0 ;
+         mi = -1 ;
+         goto downstack ;
+      }
+upstack:
+      if (solvestates.size() == 0)
+         return v ;
+      {
+         auto &ss = solvestates[solvestates.size()-1] ;
+         togo++ ;
+         sp-- ;
+         st = ss.st ;
+         mi = ss.mi ;
+         mask = ss.mask ;
+         skipbase = ss.skipbase ;
+      }
+      solvestates.pop_back() ;
+      if (v == 1)
+         goto upstack ;
+      if (!quarter && v == -1) {
+         m = randomstart ? randomized[togo][mi] : mi ;
+         if (pd.moves[m].base < 64)
+            skipbase |= 1LL << pd.moves[m].base ;
+      }
+downstack:
+      mi++ ;
+      if (mi >= (int)pd.moves.size()) {
+         v = 0 ;
+         goto upstack ;
+      }
       m = randomstart ? randomized[togo][mi] : mi ;
-      if (pd.moves[m].base < 64)
-         skipbase |= 1LL << pd.moves[m].base ;
-   }
-topm:
-   mi++ ;
-   if (mi >= (int)pd.moves.size()) {
-      v = 0 ;
-      goto returnval ;
-   }
-   m = randomstart ? randomized[togo][mi] : mi ;
-   {
       const moove &mv = pd.moves[m] ;
       if (!quarter && mv.base < 64 && ((skipbase >> mv.base) & 1))
-         goto topm ;
+         goto downstack ;
       if ((mask >> mv.cs) & 1)
-         goto topm ;
+         goto downstack ;
       pd.mul(posns[sp], mv.pos, posns[sp+1]) ;
       if (!pd.legalstate(posns[sp+1]))
-         goto topm ;
+         goto downstack ;
       movehist[sp] = m ;
       solvestates.push_back({st, mi, mask, skipbase}) ;
       togo-- ;
       sp++ ;
       st = canonnext[st][mv.cs] ;
-      goto top ;
    }
 }
 int solveworker::solvestart(const puzdef &pd, prunetable &pt, int w) {