diff --git a/compiler/sparcgen/cpubase.pas b/compiler/sparcgen/cpubase.pas
index d544806071..a3811c7bfc 100644
--- a/compiler/sparcgen/cpubase.pas
+++ b/compiler/sparcgen/cpubase.pas
@@ -218,12 +218,21 @@ uses
                           Default generic sizes
 *****************************************************************************}
 
+{$ifdef SPARC64}
+      {# Defines the default address size for a processor, }
+      OS_ADDR = OS_64;
+      {# the natural int size for a processor,
+         has to match osuinttype/ossinttype as initialized in psystem }
+      OS_INT = OS_64;
+      OS_SINT = OS_S64;
+{$else SPARC64}
       {# Defines the default address size for a processor, }
       OS_ADDR = OS_32;
       {# the natural int size for a processor,
          has to match osuinttype/ossinttype as initialized in psystem }
       OS_INT = OS_32;
       OS_SINT = OS_S32;
+{$endif SPARC64}
       {# the maximum float size for a processor,           }
       OS_FLOAT = OS_F64;
       {# the size of a vector register for a processor     }