- VarAdd, VarMul: I4 overflows to R8 and not I8 even if the result

would fit in I8. Fix tests.
- Document a brokeness in the handling of I8 numbers in
  VarNumFromParseNum. Fix tests.

dlls/oleaut32/tests/vartest.c

@@ -1187,7 +1187,10 @@ static void test_VarNumFromParseNum(void)
   SETRGB(12, 0xf); SETRGB(13, 0xf); SETRGB(14, 0xf); SETRGB(15, 0xf);
   if (HAVE_OLEAUT32_I8)
   {
-    CONVERT(16,0,0,16,4,0, INTEGER_VTBITS); EXPECT_I8(0x7fffffff,0xffffffff);
+    /* We cannot use INTEGER_VTBITS as WinXP and Win2003 are broken(?). They
+       truncate the number to the smallest integer size requested:
+       CONVERT(16,0,0,16,4,0, INTEGER_VTBITS); EXPECT_I1((signed char)0xff); */
+    CONVERT(16,0,0,16,4,0, VTBIT_I8); EXPECT_I8(0x7fffffff,0xffffffff);
   }
 
   /* Assume the above pattern holds for numbers without hi-bit set, test (preservation of) hi-bit */
@@ -1210,7 +1213,11 @@ static void test_VarNumFromParseNum(void)
   SETRGB(12, 0); SETRGB(13, 0); SETRGB(14, 0); SETRGB(15, 2);
   if (HAVE_OLEAUT32_I8)
   {
-    CONVERT(16,0,0,16,4,0, INTEGER_VTBITS); EXPECT_I8(0x80000000,0x00000002);
+    /* We cannot use INTEGER_VTBITS as WinXP and Win2003 are broken(?). They
+       truncate the number to the smallest integer size requested:
+       CONVERT(16,0,0,16,4,0, INTEGER_VTBITS & ~VTBIT_I1);
+       EXPECT_I2((signed short)0x0002); */
+    CONVERT(16,0,0,16,4,0, VTBIT_I8); EXPECT_I8(0x80000000,0x00000002);
   }
 
   /* Test (preservation of) hi-bit with STRICT type requesting */
@@ -4684,15 +4691,9 @@ static void test_VarMul(void)
     VARMUL(I2, I2_MAX, I2, I2_MAX, I4, I2_MAX * I2_MAX);
     VARMUL(I2, I2_MAX, I2, I2_MIN, I4, I2_MAX * I2_MIN);
     VARMUL(I2, I2_MIN, I2, I2_MIN, I4, I2_MIN * I2_MIN);
-if (HAVE_OLEAUT32_I8) {
-    VARMUL(I4, I4_MAX, I4, I4_MAX, I8, (LONGLONG)I4_MAX * I4_MAX);
-    VARMUL(I4, I4_MAX, I4, I4_MIN, I8, (LONGLONG)I4_MAX * I4_MIN);
-    VARMUL(I4, I4_MIN, I4, I4_MIN, I8, (LONGLONG)I4_MIN * I4_MIN);
-} else {
     VARMUL(I4, I4_MAX, I4, I4_MAX, R8, (double)I4_MAX * I4_MAX);
     VARMUL(I4, I4_MAX, I4, I4_MIN, R8, (double)I4_MAX * I4_MIN);
     VARMUL(I4, I4_MIN, I4, I4_MIN, R8, (double)I4_MIN * I4_MIN);
-}
     VARMUL(R4, R4_MAX, R4, R4_MAX, R8, (double)R4_MAX * R4_MAX);
     VARMUL(R4, R4_MAX, R4, R4_MIN, R4, R4_MAX * R4_MIN);
     VARMUL(R4, R4_MIN, R4, R4_MIN, R4, R4_MIN * R4_MIN);
@@ -4878,13 +4879,8 @@ static void test_VarAdd(void)
     VARADD(I2, I2_MAX, I2, I2_MIN, I2, I2_MAX + I2_MIN);
     VARADD(I2, I2_MIN, I2, I2_MIN, I4, I2_MIN + I2_MIN);
     VARADD(I4, I4_MAX, I4, I4_MIN, I4, I4_MAX + I4_MIN);
-    if (HAVE_OLEAUT32_I8) {
-        VARADD(I4, I4_MAX, I4, I4_MAX, I8, (LONGLONG)I4_MAX + I4_MAX);
-        VARADD(I4, I4_MIN, I4, I4_MIN, I8, (LONGLONG)I4_MIN + I4_MIN);
-    } else {
     VARADD(I4, I4_MAX, I4, I4_MAX, R8, (double)I4_MAX + I4_MAX);
     VARADD(I4, I4_MIN, I4, I4_MIN, R8, (double)I4_MIN + I4_MIN);
-    }
     VARADD(R4, R4_MAX, R4, R4_MAX, R8, (double)R4_MAX + R4_MAX);
     VARADD(R4, R4_MAX, R4, R4_MIN, R4, R4_MAX + R4_MIN);
     VARADD(R4, R4_MIN, R4, R4_MIN, R4, R4_MIN + R4_MIN);

dlls/oleaut32/variant.c

@@ -1926,6 +1926,11 @@ HRESULT WINAPI VarParseNumFromStr(OLECHAR *lpszStr, LCID lcid, ULONG dwFlags,
  *  - Rounding (dropping of decimal points) occurs without error. See VarI8FromR8()
  *    for details of the rounding method.
  *  - pVarDst is not cleared before the result is stored in it.
+ *  - WinXP and Win2003 support VTBIT_I8, VTBIT_UI8 but that's buggy (by
+ *    design?): If some other VTBIT's for integers are specified together
+ *    with VTBIT_I8 and the number will fit only in a VT_I8 Windows will "cast"
+ *    the number to the smallest requested integer truncating this way the
+ *    number.  Wine dosn't implement this "feature" (yet?).
  */
 HRESULT WINAPI VarNumFromParseNum(NUMPARSE *pNumprs, BYTE *rgbDig,
                                   ULONG dwVtBits, VARIANT *pVarDst)
@@ -2893,7 +2898,11 @@ HRESULT WINAPI VarAdd(LPVARIANT left, LPVARIANT right, LPVARIANT result)
     }
     if (resvt != tvt) {
         if ((hres = VariantChangeType(result, &tv, 0, resvt)) != S_OK) {
-            /* Overflow! Change to the vartype with the next higher priority */
+            /* Overflow! Change to the vartype with the next higher priority.
+               With one exception: I4 ==> R8 even if it would fit in I8 */
+            if (resvt == VT_I4)
+                resvt = VT_R8;
+            else
                 resvt = prio2vt[coerce[resvt] + 1];
             hres = VariantChangeType(result, &tv, 0, resvt);
         }
@@ -3061,7 +3070,11 @@ HRESULT WINAPI VarMul(LPVARIANT left, LPVARIANT right, LPVARIANT result)
     }
     if (resvt != tvt) {
         while ((hres = VariantChangeType(result, &tv, 0, resvt)) != S_OK) {
-            /* Overflow! Change to the vartype with the next higher priority */
+            /* Overflow! Change to the vartype with the next higher priority.
+               With one exception: I4 ==> R8 even if it would fit in I8 */
+            if (resvt == VT_I4)
+                resvt = VT_R8;
+            else
                 resvt = prio2vt[coerce[resvt] + 1];
         }
     } else