diff --git a/src/hb-subset-instancer-solver.cc b/src/hb-subset-instancer-solver.cc
index 4cb3f8a48..4876bc437 100644
--- a/src/hb-subset-instancer-solver.cc
+++ b/src/hb-subset-instancer-solver.cc
@@ -168,12 +168,14 @@ _solve (Triple tent, Triple axisLimit, bool negative = false)
    *                           |
    *                      crossing
    */
-  if (gain > outGain)
+  if (gain >= outGain)
   {
+    // Note that this is the branch taken if both gain and outGain are 0.
+
     // Crossing point on the axis.
     float crossing = peak + (1 - gain) * (upper - peak);
 
-    Triple loc{axisDef, peak, crossing};
+    Triple loc{hb_max (lower, axisDef), peak, crossing};
     float scalar = 1.f;
 
     // The part before the crossing point.
@@ -253,7 +255,7 @@ _solve (Triple tent, Triple axisLimit, bool negative = false)
      *              axisDef      axisMax
      */
     float newUpper = peak + (1 - gain) * (upper - peak);
-    assert (axisMax <= newUpper);  // Because outGain >= gain
+    assert (axisMax <= newUpper);  // Because outGain > gain
     if (newUpper <= axisDef + (axisMax - axisDef) * 2)
     {
       upper = newUpper;
diff --git a/src/test-subset-instancer-solver.cc b/src/test-subset-instancer-solver.cc
index e8294cfa8..f68a7deb4 100644
--- a/src/test-subset-instancer-solver.cc
+++ b/src/test-subset-instancer-solver.cc
@@ -411,5 +411,15 @@ main (int argc, char **argv)
     assert (out[0].first == 1.f);
     assert (out[0].second == Triple (0.5f, 1.f, 1.f));
   }
+
+  {
+    Triple tent (0.6f, 0.7f, 0.8f);
+    Triple axis_range (-1.f, 0.2f, 1.f);
+    TripleDistances axis_distances{1.f, 1.f};
+    result_t out = rebase_tent (tent, axis_range, axis_distances);
+    assert (out.length == 1);
+    assert (out[0].first == 1.f);
+    assert (out[0].second == Triple (0.5f, 0.625f, 0.75f));
+  }
 }