diff --git a/cast.hpp b/cast.hpp
index fe928c8d..ff4ba02d 100644
--- a/cast.hpp
+++ b/cast.hpp
@@ -107,6 +107,14 @@ namespace cruft::cast {
     lossless (const SrcT &src)
     {
 #ifndef NDEBUG
+        // GCC insists that the initial static_cast to DstT is a floating
+        // point comparison if we pass in a bool and a float.
+        //
+        // The only way around this is to ignore the warning locally (we use
+        // almost_equal inside CHECK_EQ anyway, so it should not be a concern).
+        #pragma GCC diagnostic push
+        #pragma GCC diagnostic ignored "-Wfloat-equal"
+
         auto dst = static_cast<DstT> (src);
 
         if constexpr (std::is_floating_point_v<SrcT>) {
@@ -120,6 +128,8 @@ namespace cruft::cast {
         // Cast dst back to src to check round-trip conversion
         // is lossless.
         CHECK_EQ (static_cast<SrcT> (dst), src);
+
+        #pragma GCC diagnostic pop
         return dst;
 #else
 #pragma GCC diagnostic push