sanity-check $Config{drand01} in rand.t

p4raw-id: //depot/perl@2085

diff --git a/t/op/rand.t b/t/op/rand.t
index a68559f..2f02d34 100755 (executable)
--- a/t/op/rand.t
+++ b/t/op/rand.t
@@ -52,6 +52,17 @@ sub bits ($) {
     $max = $min = rand(1);
     for (1..$reps) {
        my $n = rand(1);
+       if ($n < 0.0 or $n >= 1.0) {
+           print <<EOM;
+# WHOA THERE!  \$Config{drand01} is set to '$Config{drand01}',
+# but that apparently produces values < 0.0 or >= 1.0.
+# Make sure \$Config{drand01} is a valid expression in the
+# C-language, and produces values in the range [0.0,1.0).
+#
+# I give up.
+EOM
+           exit;
+       }
        $sum += $n;
        $bits += bits($n * 256);        # Don't be greedy; 8 is enough
                    # It's too many if randbits is less than 8!
@@ -75,7 +86,7 @@ sub bits ($) {
     # wrong value is that Config.pm is incorrect.)
     #
     if ($max <= 0 or $max >= (2 ** $randbits)) {# Just in case...
-       print "not ok 1\n";
+       print "# max=[$max] min=[$min]\nnot ok 1\n";
        print "# This perl was compiled with randbits=$randbits\n";
        print "# which is _way_ off. Or maybe your system rand is broken,\n";
        print "# or your C compiler can't multiply, or maybe Martians\n";
@@ -91,7 +102,7 @@ sub bits ($) {
     $off = int($off) + ($off > 0);             # Next more positive int
     if ($off) {
        $shouldbe = $Config{randbits} + $off;
-       print "not ok 1\n";
+       print "# max=[$max] min=[$min]\nnot ok 1\n";
        print "# This perl was compiled with randbits=$randbits on $^O.\n";
        print "# Consider using randbits=$shouldbe instead.\n";
        # And skip the remaining tests; they would be pointless now.

diff --git a/win32/config.bc b/win32/config.bc
index 7f27132..69620ab 100644 (file)
--- a/win32/config.bc
+++ b/win32/config.bc
@@ -331,7 +331,7 @@ direntrytype='struct direct'
 dlext='dll'
 dlsrc='dl_win32.xs'
 doublesize='8'
-drand01='rand()'
+drand01='(rand()/(double)((unsigned)1<<RANDBITS))'
 dynamic_ext='Socket IO Fcntl Opcode SDBM_File attrs Thread'
 eagain='EAGAIN'
 ebcdic='undef'

diff --git a/win32/config.gc b/win32/config.gc
index cd349c7..7dc64f8 100644 (file)
--- a/win32/config.gc
+++ b/win32/config.gc
@@ -331,7 +331,7 @@ direntrytype='struct direct'
 dlext='dll'
 dlsrc='dl_win32.xs'
 doublesize='8'
-drand01='rand()'
+drand01='(rand()/(double)((unsigned)1<<RANDBITS))'
 dynamic_ext='Socket IO Fcntl Opcode SDBM_File attrs Thread'
 eagain='EAGAIN'
 ebcdic='undef'

diff --git a/win32/config.vc b/win32/config.vc
index 8d7e741..c9ef76c 100644 (file)
--- a/win32/config.vc
+++ b/win32/config.vc
@@ -331,7 +331,7 @@ direntrytype='struct direct'
 dlext='dll'
 dlsrc='dl_win32.xs'
 doublesize='8'
-drand01='rand()'
+drand01='(rand()/(double)((unsigned)1<<RANDBITS))'
 dynamic_ext='Socket IO Fcntl Opcode SDBM_File attrs Thread'
 eagain='EAGAIN'
 ebcdic='undef'

diff --git a/win32/config_H.bc b/win32/config_H.bc
index 493da73..8c06b36 100644 (file)
--- a/win32/config_H.bc
+++ b/win32/config_H.bc
@@ -1348,7 +1348,7 @@
  *     function used to generate normalized random numbers.
  *     Values include 15, 16, 31, and 48.
  */
-#define Drand01()              rand()          /**/
+#define Drand01()              (rand()/(double)((unsigned)1<<RANDBITS))                /**/
 #define Rand_seed_t            unsigned                /**/
 #define seedDrand01(x) srand((Rand_seed_t)x)   /**/
 #define RANDBITS               15              /**/

diff --git a/win32/config_H.gc b/win32/config_H.gc
index aac2416..82e5d18 100644 (file)
--- a/win32/config_H.gc
+++ b/win32/config_H.gc
@@ -1348,7 +1348,7 @@
  *     function used to generate normalized random numbers.
  *     Values include 15, 16, 31, and 48.
  */
-#define Drand01()              rand()          /**/
+#define Drand01()              (rand()/(double)((unsigned)1<<RANDBITS))                /**/
 #define Rand_seed_t            unsigned                /**/
 #define seedDrand01(x) srand((Rand_seed_t)x)   /**/
 #define RANDBITS               15              /**/

diff --git a/win32/config_H.vc b/win32/config_H.vc
index 3c6d368..82d6218 100644 (file)
--- a/win32/config_H.vc
+++ b/win32/config_H.vc
@@ -1348,7 +1348,7 @@
  *     function used to generate normalized random numbers.
  *     Values include 15, 16, 31, and 48.
  */
-#define Drand01()              rand()          /**/
+#define Drand01()              (rand()/(double)((unsigned)1<<RANDBITS))                /**/
 #define Rand_seed_t            unsigned                /**/
 #define seedDrand01(x) srand((Rand_seed_t)x)   /**/
 #define RANDBITS               15              /**/