diff --git a/lapack/gonum/lapack.go b/lapack/gonum/lapack.go
index 434da02d..950db32c 100644
--- a/lapack/gonum/lapack.go
+++ b/lapack/gonum/lapack.go
@@ -37,6 +37,8 @@ func abs(a int) int {
 const (
 	// dlamchE is the machine epsilon. For IEEE this is 2^{-53}.
 	dlamchE = 1.0 / (1 << 53)
+	// TODO(kortschak) Replace this with 0x1p-53 when go1.12 is no
+	// longer supported.
 
 	// dlamchB is the radix of the machine (the base of the number system).
 	dlamchB = 2
@@ -48,4 +50,6 @@ const (
 	// 1/dlamchS does not overflow, or also the smallest normal number.
 	// For IEEE this is 2^{-1022}.
 	dlamchS = 1.0 / (1 << 256) / (1 << 256) / (1 << 256) / (1 << 254)
+	// TODO(kortschak) Replace this with 0x1p-1022 when go1.12 is no
+	// longer supported.
 )