*: remove lots of GCC 4.8 fallback code

We can remove those C++11 and C++14 kludges because we require GCC 4.9
now.

src/util/Alloc.cxx

@@ -76,8 +76,6 @@ xstrndup(const char *s, size_t n)
 	return p;
 }
 
-#if CLANG_OR_GCC_VERSION(4,7)
-
 template<typename... Args>
 static inline size_t
 FillLengths(size_t *lengths, const char *a, Args&&... args)
@@ -107,14 +105,11 @@ StringCat(char *p, const size_t *lengths, const char *a)
 	memcpy(p, a, *lengths);
 }
 
-#endif
-
 template<typename... Args>
 gcc_malloc gcc_nonnull_all
 static inline char *
 t_xstrcatdup(Args&&... args)
 {
-#if CLANG_OR_GCC_VERSION(4,7)
 	constexpr size_t n = sizeof...(args);
 
 	size_t lengths[n];
@@ -124,22 +119,6 @@ t_xstrcatdup(Args&&... args)
 	StringCat(p, lengths, args...);
 	p[total] = 0;
 	return p;
-#else
-	/* fallback implementation for gcc 4.6, because that old
-	   compiler is too buggy to compile the above template
-	   functions */
-	const char *const argv[] = { args... };
-
-	size_t total = 0;
-	for (auto i : argv)
-		total += strlen(i);
-
-	char *p = (char *)xalloc(total + 1), *q = p;
-	for (auto i : argv)
-		q = stpcpy(q, i);
-
-	return p;
-#endif
 }
 
 char *

src/util/Cast.hxx

@@ -84,10 +84,7 @@ ContainerAttributeOffset(const A C::*p)
  * Cast the given pointer to a struct member to its parent structure.
  */
 template<class C, class A>
-#if CLANG_OR_GCC_VERSION(4,7)
-constexpr
-#endif
-static inline C &
+static inline constexpr C &
 ContainerCast(A &a, A C::*member)
 {
 	return *OffsetCast<C, A>(&a, ContainerAttributeOffset<C, A>(member));
@@ -97,10 +94,7 @@ ContainerCast(A &a, A C::*member)
  * Cast the given pointer to a struct member to its parent structure.
  */
 template<class C, class A>
-#if CLANG_OR_GCC_VERSION(4,7)
-constexpr
-#endif
-static inline const C &
+static inline constexpr const C &
 ContainerCast(const A &a, A C::*member)
 {
 	return *OffsetCast<const C, const A>(&a, ContainerAttributeOffset<C, A>(member));