2 files changed, 13 insertions, 9 deletions
diff --git a/spec/mspec/lib/mspec/guards/platform.rb b/spec/mspec/lib/mspec/guards/platform.rb
index e87b08a4c1..03c0fca8f5 100644
--- a/spec/mspec/lib/mspec/guards/platform.rb
+++ b/spec/mspec/lib/mspec/guards/platform.rb
@@ -53,23 +53,27 @@ class PlatformGuard < SpecGuard
     end
   end
 
-  WORD_SIZE = 1.size * 8
-
   POINTER_SIZE = begin
     require 'rbconfig/sizeof'
     RbConfig::SIZEOF["void*"] * 8
   rescue LoadError
-    WORD_SIZE
+    [0].pack('j').size
   end
 
-  def self.wordsize?(size)
-    size == WORD_SIZE
+  C_LONG_SIZE = if defined?(RbConfig::SIZEOF[])
+    RbConfig::SIZEOF["long"] * 8
+  else
+    [0].pack('l!').size
   end
 
   def self.pointer_size?(size)
     size == POINTER_SIZE
   end
 
+  def self.c_long_size?(size)
+    size == C_LONG_SIZE
+  end
+
   def initialize(*args)
     if args.last.is_a?(Hash)
       @options, @platforms = args.last, args[0..-2]
@@ -85,10 +89,10 @@ class PlatformGuard < SpecGuard
       case key
       when :os
         match &&= PlatformGuard.os?(*value)
-      when :wordsize
-        match &&= PlatformGuard.wordsize? value
       when :pointer_size
         match &&= PlatformGuard.pointer_size? value
+      when :c_long_size
+        match &&= PlatformGuard::c_long_size? value
       end
     end
     match
diff --git a/spec/mspec/lib/mspec/helpers/numeric.rb b/spec/mspec/lib/mspec/helpers/numeric.rb
index c1ed81a233..46d3d7b182 100644
--- a/spec/mspec/lib/mspec/helpers/numeric.rb
+++ b/spec/mspec/lib/mspec/helpers/numeric.rb
@@ -28,7 +28,7 @@ end
 # specs based on the relationship between values rather than specific
 # values.
 if PlatformGuard.standard? or PlatformGuard.implementation? :topaz
-  if PlatformGuard.wordsize? 32
+  if PlatformGuard.c_long_size? 32
     def fixnum_max
       (2**30) - 1
     end
@@ -36,7 +36,7 @@ if PlatformGuard.standard? or PlatformGuard.implementation? :topaz
     def fixnum_min
       -(2**30)
     end
-  elsif PlatformGuard.wordsize? 64
+  elsif PlatformGuard.c_long_size? 64
     def fixnum_max
       (2**62) - 1
     end