log2: Remove support for OSF/1.

* m4/log2.m4 (gl_FUNC_LOG2_WORKS): Remove test regarding log2 (-0.0).

diff --git a/ChangeLog b/ChangeLog
index b84777d915dcc7f24c1f3ebba89d59933a36a40c..134cd544560b75f5391e4d770a0d04c5b65286e3 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2025-09-09  Bruno Haible  <bruno@clisp.org>
 
+       log2: Remove support for OSF/1.
+       * m4/log2.m4 (gl_FUNC_LOG2_WORKS): Remove test regarding log2 (-0.0).
+
        log10f: Remove support for OSF/1.
        * m4/log10f.m4 (gl_FUNC_LOG10F_WORKS): Remove macro.
        (gl_FUNC_LOG10F): Don't invoke it.

diff --git a/m4/log2.m4 b/m4/log2.m4
index f481a2138add79012e623b9ade0ae69af46b6766..342c43cc033cd086f1ad6b80b61b2461044e1ace 100644 (file)
--- a/m4/log2.m4
+++ b/m4/log2.m4
@@ -1,5 +1,5 @@
 # log2.m4
-# serial 15
+# serial 16
 dnl Copyright (C) 2010-2025 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -131,7 +131,6 @@ int main (int argc, char *argv[])
 ])
 
 dnl Test whether log2() works.
-dnl On OSF/1 5.1, log2(-0.0) is NaN.
 dnl On Cygwin 1.7.9, log2(2^29) is not exactly 29.
 AC_DEFUN([gl_FUNC_LOG2_WORKS],
 [
@@ -154,23 +153,18 @@ volatile double y;
 int main ()
 {
   int result = 0;
-  /* This test fails on OSF/1 5.1.  */
-  x = -0.0;
-  y = log2 (x);
-  if (!(y + y == y))
-    result |= 1;
   /* This test fails on Cygwin 1.7.9.  */
   x = 536870912.0;
   y = log2 (x);
   if (!(y == 29.0))
-    result |= 2;
+    result |= 1;
   return result;
 }
 ]])],
         [gl_cv_func_log2_works=yes],
         [gl_cv_func_log2_works=no],
         [case "$host_os" in
-           cygwin* | osf*)    gl_cv_func_log2_works="guessing no" ;;
+           cygwin*)           gl_cv_func_log2_works="guessing no" ;;
                               # Guess yes on native Windows.
            mingw* | windows*) gl_cv_func_log2_works="guessing yes" ;;
            *)                 gl_cv_func_log2_works="guessing yes" ;;