diff --git a/alg/gdal_interpolateatpoint.cpp b/alg/gdal_interpolateatpoint.cpp
index 294516232597..171106f3fb03 100644
--- a/alg/gdal_interpolateatpoint.cpp
+++ b/alg/gdal_interpolateatpoint.cpp
@@ -377,14 +377,14 @@ bool GDALInterpolateAtPointImpl(GDALRasterBand *pBand,
     else
     {
         const gdal::Vector2i d = inLoc.cast<int>();
-        T dfOut{};
-        if (!GDALInterpExtractValuesWindow(pBand, cache, d, {1, 1}, &dfOut) ||
-            (bGotNoDataValue && areEqualReal(dfNoDataValue, dfOut)))
+        T adfOut[1] = {};
+        if (!GDALInterpExtractValuesWindow(pBand, cache, d, {1, 1}, adfOut) ||
+            (bGotNoDataValue && areEqualReal(dfNoDataValue, adfOut[0])))
         {
             return FALSE;
         }
 
-        out = dfOut;
+        out = adfOut[0];
 
         return TRUE;
     }
diff --git a/autotest/cpp/test_gdal_vectorx.cpp b/autotest/cpp/test_gdal_vectorx.cpp
index d63547ed06fc..94bb2e6c3514 100644
--- a/autotest/cpp/test_gdal_vectorx.cpp
+++ b/autotest/cpp/test_gdal_vectorx.cpp
@@ -119,7 +119,7 @@ TEST_F(test_vectorx, array)
 
 TEST_F(test_vectorx, fill)
 {
-    const auto a = gdal::Vector3d().fill(42.0);
+    const gdal::Vector3d a = gdal::Vector3d().fill(42.0);
     EXPECT_EQ(3, a.size());
     EXPECT_EQ(42.0, a[0]);
     EXPECT_EQ(42.0, a[1]);
@@ -128,7 +128,7 @@ TEST_F(test_vectorx, fill)
 
 TEST_F(test_vectorx, fill_nan)
 {
-    const auto a =
+    const gdal::Vector3d a =
         gdal::Vector3d().fill(std::numeric_limits<double>::quiet_NaN());
     EXPECT_EQ(3, a.size());
     EXPECT_TRUE(std::isnan(a[0]));