diff --git a/core/math/math-docs.factor b/core/math/math-docs.factor
index d98685fb48..97e0a1e7cf 100644
--- a/core/math/math-docs.factor
+++ b/core/math/math-docs.factor
@@ -282,12 +282,12 @@ HELP: fp-bitwise=
 { $examples
     "Not-a-number equality:"
     { $example
-        "USING: math prettyprint ;"
+        "USING: kernel math prettyprint ;"
         "0.0 0.0 / dup number= ."
         "f"
     }
     { $example
-        "USING: math prettyprint ;"
+        "USING: kernel math prettyprint ;"
         "0.0 0.0 / dup fp-bitwise= ."
         "t"
     }
@@ -299,7 +299,7 @@ HELP: fp-bitwise=
     }
     { $example
         "USING: math prettyprint ;"
-        "-0.0 0.0 = ."
+        "-0.0 0.0 number= ."
         "t"
     }
 } ;
diff --git a/core/syntax/syntax-docs.factor b/core/syntax/syntax-docs.factor
index 19e644cb68..0a11f62c16 100644
--- a/core/syntax/syntax-docs.factor
+++ b/core/syntax/syntax-docs.factor
@@ -612,8 +612,8 @@ HELP: NAN:
 { $examples
     { $example
         "USE: prettyprint"
-        "NAN: deadbeef ."
-        "NAN: deadbeef"
+        "NAN: 80000deadbeef ."
+        "NAN: 80000deadbeef"
     }
 } ;
 
diff --git a/vm/errors.cpp b/vm/errors.cpp
index 1dcee889a3..c9d2a94e56 100644
--- a/vm/errors.cpp
+++ b/vm/errors.cpp
@@ -130,9 +130,9 @@ void divide_by_zero_error()
 	general_error(ERROR_DIVIDE_BY_ZERO,F,F,NULL);
 }
 
-void fp_trap_error()
+void fp_trap_error(stack_frame *signal_callstack_top)
 {
-	general_error(ERROR_FP_TRAP,F,F,NULL);
+	general_error(ERROR_FP_TRAP,F,F,signal_callstack_top);
 }
 
 PRIMITIVE(call_clear)
@@ -158,7 +158,7 @@ void misc_signal_handler_impl()
 
 void fp_signal_handler_impl()
 {
-    fp_trap_error();
+	fp_trap_error(signal_callstack_top);
 }
 
 }
diff --git a/vm/mach_signal.cpp b/vm/mach_signal.cpp
index 50a924f8e4..facf512b77 100644
--- a/vm/mach_signal.cpp
+++ b/vm/mach_signal.cpp
@@ -55,12 +55,12 @@ static void call_fault_handler(
 		MACH_PROGRAM_COUNTER(thread_state) = (cell)memory_signal_handler_impl;
 	}
 	else if(exception == EXC_ARITHMETIC && code != MACH_EXC_INTEGER_DIV)
-    {
+	{
 		MACH_PROGRAM_COUNTER(thread_state) = (cell)fp_signal_handler_impl;
-    }
-    else
-    {
-        signal_number = exception == EXC_ARITHMETIC ? SIGFPE : SIGABRT;
+	}
+	else
+	{
+		signal_number = (exception == EXC_ARITHMETIC ? SIGFPE : SIGABRT);
 		MACH_PROGRAM_COUNTER(thread_state) = (cell)misc_signal_handler_impl;
 	}
 }