diff --git a/3rdparty/libtiff/tif_aux.c b/3rdparty/libtiff/tif_aux.c
index 927150a493..7d3af1bb59 100644
--- a/3rdparty/libtiff/tif_aux.c
+++ b/3rdparty/libtiff/tif_aux.c
@@ -325,8 +325,8 @@ _TIFFUInt64ToFloat(uint64 ui64)
 	if (i.part.high >= 0) {
 		return (float)i.value;
 	} else {
-		long double df;
-		df = (long double)i.value;
+		double df;
+		df = (double)i.value;
 		df += 18446744073709551616.0; /* adding 2**64 */
 		return (float)df;
 	}
@@ -341,8 +341,8 @@ _TIFFUInt64ToDouble(uint64 ui64)
 	if (i.part.high >= 0) {
 		return (double)i.value;
 	} else {
-		long double df;
-		df = (long double)i.value;
+		double df;
+		df = (double)i.value;
 		df += 18446744073709551616.0; /* adding 2**64 */
 		return (double)df;
 	}
diff --git a/modules/flann/include/opencv2/flann/dist.h b/modules/flann/include/opencv2/flann/dist.h
index 30d6da7d9e..d76cdb66fc 100644
--- a/modules/flann/include/opencv2/flann/dist.h
+++ b/modules/flann/include/opencv2/flann/dist.h
@@ -59,10 +59,6 @@ inline float abs<float>(float x) { return fabsf(x); }
 template<>
 inline double abs<double>(double x) { return fabs(x); }
 
-template<>
-inline long double abs<long double>(long double x) { return fabsl(x); }
-
-
 template<typename T>
 struct Accumulator { typedef T Type; };
 template<>
diff --git a/modules/flann/include/opencv2/flann/hdf5.h b/modules/flann/include/opencv2/flann/hdf5.h
index ff92434158..ef3e999738 100644
--- a/modules/flann/include/opencv2/flann/hdf5.h
+++ b/modules/flann/include/opencv2/flann/hdf5.h
@@ -67,8 +67,6 @@ template<>
 hid_t get_hdf5_type<float>() { return H5T_NATIVE_FLOAT; }
 template<>
 hid_t get_hdf5_type<double>() { return H5T_NATIVE_DOUBLE; }
-template<>
-hid_t get_hdf5_type<long double>() { return H5T_NATIVE_LDOUBLE; }
 }