diff --git a/gen/asm-x86-32.h b/gen/asm-x86-32.h
index ecfd380b..b251d18d 100644
--- a/gen/asm-x86-32.h
+++ b/gen/asm-x86-32.h
@@ -1436,6 +1436,10 @@ struct AsmProcessor
                             break;
                         }
 
+                        // osx needs an extra underscore
+                        if (global.params.os == OSMacOSX)
+                            insnTemplate->writestring("_");
+
                         // print out the mangle
                         insnTemplate->writestring(vd->mangle());
                         vd->nakedUse = true;
diff --git a/gen/asm-x86-64.h b/gen/asm-x86-64.h
index a17a7352..2737af07 100644
--- a/gen/asm-x86-64.h
+++ b/gen/asm-x86-64.h
@@ -1556,6 +1556,10 @@ struct AsmProcessor
                             break;
                         }
 
+                        // osx needs an extra underscore
+                        if (global.params.os == OSMacOSX)
+                            insnTemplate->writestring("_");
+
                         // print out the mangle
                         insnTemplate->writestring(vd->mangle());
                         vd->nakedUse = true;