Import Upstream version 2.72.4

glib/gnulib/gl_cv_func_frexp_works/meson.build

@@ -0,0 +1,110 @@
+# Copyright (C) 2002-2004, 2006-2018 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+frexp_test = '''
+#define HAVE_DECL_ALARM 0
+#include <float.h>
+#include <math.h>
+#include <string.h>
+#if HAVE_DECL_ALARM
+# include <signal.h>
+# include <unistd.h>
+#endif
+/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
+   ICC 10.0 has a bug when optimizing the expression -zero.
+   The expression -DBL_MIN * DBL_MIN does not work when cross-compiling
+   to PowerPC on Mac OS X 10.5.  */
+#if defined __hpux || defined __sgi || defined __ICC
+static double
+compute_minus_zero (void)
+{
+  return -DBL_MIN * DBL_MIN;
+}
+# define minus_zero compute_minus_zero ()
+#else
+double minus_zero = -0.0;
+#endif
+int main()
+{
+  int result = 0;
+  int i;
+  volatile double x;
+  double zero = 0.0;
+#if HAVE_DECL_ALARM
+  /* NeXTstep 3.3 frexp() runs into an endless loop when called on an infinite
+     number.  Let the test fail in this case.  */
+  signal (SIGALRM, SIG_DFL);
+  alarm (5);
+#endif
+  /* Test on denormalized numbers.  */
+  for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5)
+    ;
+  if (x > 0.0)
+    {
+      int exp;
+      double y = frexp (x, &exp);
+      /* On machines with IEEE754 arithmetic: x = 1.11254e-308, exp = -1022.
+         On NetBSD: y = 0.75. Correct: y = 0.5.  */
+      if (y != 0.5)
+        result |= 1;
+    }
+  /* Test on infinite numbers.  */
+  x = 1.0 / zero;
+  {
+    int exp;
+    double y = frexp (x, &exp);
+    if (y != x)
+      result |= 2;
+  }
+  /* Test on negative zero.  */
+  x = minus_zero;
+  {
+    int exp;
+    double y = frexp (x, &exp);
+    if (memcmp (&y, &x, sizeof x))
+      result |= 4;
+  }
+  x = 0.0;
+  {
+    int exp;
+    double y = frexp (x, &exp);
+    if (memcmp (&y, &x, sizeof x))
+      result |= 8;
+  }
+  return result;
+}'''
+
+if not meson.is_cross_build() or meson.has_exe_wrapper()
+  run_result = cc.run(frexp_test,
+      name : 'frexp works',
+      dependencies : [libm])
+  rc = run_result.returncode()
+  gl_cv_func_frexp_works = run_result.compiled() and rc == 0
+  gl_cv_func_frexp_broken_beyond_repair = not gl_cv_func_frexp_works
+# bit 1 is not set
+  if (rc == 1 or rc == 3 or rc == 5 or rc == 9 or
+      rc == 7 or rc == 11 or rc == 13)
+    gl_cv_func_frexp_broken_beyond_repair = true
+  else
+    gl_cv_func_frexp_broken_beyond_repair = false
+  endif
+else
+  if (host_system.startswith ('netbsd') or
+      host_system.startswith ('irix'))
+    gl_cv_func_frexp_works = false
+    gl_cv_func_frexp_broken_beyond_repair = true
+  elif host_system == 'windows'
+    if cc.get_id () == 'msvc' or cc.get_id() == 'clang-cl'
+      gl_cv_func_frexp_works = true
+      gl_cv_func_frexp_broken_beyond_repair = false
+    else
+      gl_cv_func_frexp_works = false
+      gl_cv_func_frexp_broken_beyond_repair = false
+    endif
+  else
+    gl_cv_func_frexp_works = true
+    gl_cv_func_frexp_broken_beyond_repair = false
+  endif
+endif