Add more checks used by Qt

libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_RDRND.h

@@ -0,0 +1,21 @@
+// HAVE_RDRND : HAVE_AVX2
+
+#undef HAVE_RDRND
+
+/* GCC, Clang: -mrdrnd
+ *
+ * MSVC: No controlling compiler option nor indicating macro. The
+ *       documentation murkily says it's always enabled on Intel and only
+ *       Intel processors; see:
+ *       https://docs.microsoft.com/en-us/cpp/intrinsics/x86-intrinsics-list
+ *       https://docs.microsoft.com/en-us/cpp/intrinsics/x64-amd64-intrinsics-list)
+ *
+ *       According to Qt, all processors that support AVX2 support RDRND so
+ *       follow their lead by assuming it's available if AVX2 is.
+ *
+ *       Note that RDRND intrinsics were added to Visual C++ 2015 according to
+ *       Wikipedia.
+ */
+#if defined(__RDRND__) || (defined(_MSC_VER) && defined(HAVE_AVX2))
+#  define HAVE_RDRND 1
+#endif

libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_RDSEED.h

@@ -0,0 +1,15 @@
+// HAVE_RDSEED
+
+#undef HAVE_RDSEED
+
+/* GCC, Clang: -mrdseed
+ *
+ * MSVC: No controlling compiler option nor indicating macro. The
+ *       documentation murkily says it's always enabled on Intel and only
+ *       Intel processors; see:
+ *       https://docs.microsoft.com/en-us/cpp/intrinsics/x86-intrinsics-list
+ *       https://docs.microsoft.com/en-us/cpp/intrinsics/x64-amd64-intrinsics-list)
+ */
+#ifdef __RDSEED__
+#  define HAVE_RDSEED 1
+#endif

libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_SIGNALING_NAN.h

@@ -0,0 +1,9 @@
+// HAVE_SIGNALING_NAN
+
+#undef HAVE_SIGNALING_NAN
+
+/* Whether implementation's double fulfills the requirements of IEC 559 which
+ * was released in 2008. See
+ * https://en.cppreference.com/w/cpp/types/numeric_limits/is_iec559.
+ */
+#define HAVE_SIGNALING_NAN 1

libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_THREADSAFE_CLOEXEC.h

@@ -0,0 +1,19 @@
+// HAVE_THREADSAFE_CLOEXEC
+
+#undef HAVE_THREADSAFE_CLOEXEC
+
+/* Define if file descriptor-creating functions taking a *_CLOEXEC flag are
+ * available. Setting the FD_CLOEXEC flag in a separate fcntl() call opens a
+ * window for another thread to fork/exec.
+ *
+ * The set of functions covered by this check are pipe2(), dup3(), accept4(),
+ * and a version of socket() which takes the SOCK_CLOEXEC flag.
+ *
+ * Since glibc 2.10, FreeBSD 10, OpenBSD 5.7, NetBSD 6.0.
+ */
+#if BUILD2_AUTOCONF_GLIBC_PREREQ(2, 10)    || \
+    BUILD2_AUTOCONF_FREEBSD_PREREQ(10, 0)  || \
+    BUILD2_AUTOCONF_OPENBSD_PREREQ(201507) || \
+    BUILD2_AUTOCONF_NETBSD_PREREQ(6, 0)
+#  define HAVE_THREADSAFE_CLOEXEC 1
+#endif

libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_XOP.h

@@ -5,7 +5,7 @@
 /* GCC, Clang: -mxop
  *
  * MSVC: No controlling compiler option nor indicating macro. The
- *       documnetation is murkily says it's always enabled on AMD and only AMD
+ *       documentation murkily says it's always enabled on AMD and only AMD
  *       processors; see:
  *       https://docs.microsoft.com/en-us/cpp/intrinsics/x86-intrinsics-list
  *       https://docs.microsoft.com/en-us/cpp/intrinsics/x64-amd64-intrinsics-list)