shithub: femtolisp

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adding divide by 0 check in div

--- a/femtolisp/cvalues.c

+++ b/femtolisp/cvalues.c

@@ -1264,6 +1264,12 @@

     return 1;

 }

+static void DivideByZeroError() __attribute__ ((__noreturn__));

+static void DivideByZeroError()

+{

+    lerror(DivideError, "/: division by zero");

+}

+

 static value_t fl_div2(value_t a, value_t b)

 {

     double da, db;

@@ -1280,7 +1286,7 @@

     db = conv_to_double(bptr, tb);

     if (db == 0 && tb < T_FLOAT)  // exact 0

-        lerror(DivideError, "/: division by zero");

+        DivideByZeroError();

     da = da/db;

@@ -1330,7 +1336,7 @@

     return return_from_int64(conv_to_int64(aptr, ta) / b64);

  div_error:

-    lerror(DivideError, "/: division by zero");

+    DivideByZeroError();

 }

 static value_t fl_bitwise_op(value_t a, value_t b, int opcode, char *fname)

--- a/femtolisp/flisp.c

+++ b/femtolisp/flisp.c

@@ -1139,8 +1139,10 @@

             goto next_op;

         case OP_IDIV:

             v = Stack[SP-2]; e = Stack[SP-1];

-            if (bothfixnums(v, e))

+            if (bothfixnums(v, e)) {

+                if (e==0) DivideByZeroError();

                 v = fixnum(numval(v) / numval(e));

+            }

             else

                 v = fl_idiv2(v, e);

             POPN(1);

--- a/femtolisp/todo

+++ b/femtolisp/todo

@@ -1024,13 +1024,13 @@

 * make (for ...) a special form

 * trycatch should require 2nd arg to be a lambda expression

 * immediate load int8 instruction

-- fix equal? on functions

-- store function name and signature

-- maxstack calculation, replace Stack with C stack, alloca

+- maxstack calculation, make Stack growable

   - stack traces and better debugging support

+- let eversion

 - lambda lifting

 * let optimization

-- let eversion

+- fix equal? on functions

+- store function name and signature

 * have macroexpand use its own global syntax table

 * be able to create/load an image file

 * fix trace and untrace