From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 29 Aug 2021 10:33:54 +0000 (+0300)
Subject: Perform bit conversion using standard-sanctioned memcpy method
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=708ef339d3e4d3661c8b3a75e3b01bafbed0f568;p=libs%2Fdatafile.git

Perform bit conversion using standard-sanctioned memcpy method

The compiler should be able to optimize it away.
---

diff --git a/source/binfloat.h b/source/binfloat.h
index 2c74441..e50b320 100644
--- a/source/binfloat.h
+++ b/source/binfloat.h
@@ -29,9 +29,6 @@ struct BinFloat
 	template<typename T>
 	struct MatchingInt;
 
-	template<typename T>
-	union Conversion;
-
 	bool sign;
 	bool infinity;
 	int exponent;
@@ -54,27 +51,21 @@ struct BinFloat::MatchingInt<float> { typedef std::uint32_t Type; };
 template<>
 struct BinFloat::MatchingInt<double> { typedef std::uint64_t Type; };
 
-template<typename T>
-union BinFloat::Conversion
-{
-	T f;
-	typename MatchingInt<T>::Type i;
-};
-
 template<typename T>
 inline BinFloat BinFloat::explode_iec559(T v)
 {
-	Conversion<T> c;
-	c.f = v;
-	return explode(c.i, sizeof(T)*CHAR_BIT);
+	typename MatchingInt<T>::Type i;
+	memcpy(&v, &i, sizeof(T));
+	return explode(i, sizeof(T)*CHAR_BIT);
 }
 
 template<typename T>
 inline T BinFloat::compose_iec559()
 {
-	Conversion<T> c;
-	c.i = compose(sizeof(T)*CHAR_BIT);
-	return c.f;
+	typename MatchingInt<T>::Type i = compose(sizeof(T)*CHAR_BIT);
+	T v;
+	memcpy(&v, &i, sizeof(T));
+	return v;
 }
 
 } // namespace DataFile