diff --git a/source/lib/detect.cpp b/source/lib/detect.cpp
index 5ed506ba54..265ed03a26 100755
--- a/source/lib/detect.cpp
+++ b/source/lib/detect.cpp
@@ -165,10 +165,16 @@ void cpu_init()
 	// note: passing a flag *disables* that exception.
 	_control87(_EM_INVALID|_EM_DENORMAL|_EM_OVERFLOW|_EM_UNDERFLOW|_EM_INEXACT, _MCW_EM);
 
+#if OS_WIN
+	// On Windows:
 	// round toward zero (truncate). this is what ANSI C calls for;
 	// if we set it to this (default is round to nearest), the compiler can
 	// generate FISTP (much faster) instead of _ftol2 with the same results.
+	//
+	// Don't do this anywhere else unless the implications have been fully
+	// investigated.
 	_control87(_RC_CHOP, _MCW_RC);
+#endif
 
 	// If possible, hook up capability-sensitive assembler routines
 	ia32_hook_capabilities();