Bug or not? Boolean warning. Can you help me make sure it is? [SOLVED]

[xlucas]

It seems FreeBasic is issuing a warning about boolean comparisons when combined logically with another, non-boolean, comparison, even though there clearly isn't a problem. But maybe I'm seeing it wrong. When I try to do something like this:

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Dim b As Boolean, n As Short

If b And n = 5 Then
    'Some statements
End If

I get a warning that reads: "Mixing operand data types may have undefined results"

OK, then I think, maybe it's associating b with n, trying to solve the And before the =, but then it should be an error, not a warning. The program runs fine, despite the warning. So I try to make things clearer like this:

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If b = True And n = 5 Then

Same thing. I try parentheses.... I try AndAlso.... I try changing the order.... In the end, the only solution is to create an If block inside another If block. I have just installed FreeBasic from the site. Take a look at these tests:

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Dim p As Boolean, c As Short

If p And c = 1 Then Print "Hello"
If p = True And c = 1 Then Print "Hello"
If p AndAlso c = 1 Then Print "Hello"
If p = True AndAlso c = 1 Then Print "Hello"
If (c = 1) And p Then Print "Hello"
If c = 1 AndAlso p = True Then Print "Hello"
If (c = 1) AndAlso (p = True) Then Print "Hello"
GetKey

All issue the warning

[sancho2]

Try:

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If b = True And cbool(n = 5) Then

This is known and it is talked about in this forum. I will see if I can find the thread and report back.

Found it
FXM says:

Most of time, the operator "=" (Equal) returns an Integer presently.
(exception: a boolean is returned only if the compared expressions are both booleans)

[fxm]

Found it
FXM says:

Most of time, the operator "=" (Equal) returns an Integer presently.
(exception: a boolean is returned only if the compared expressions are both booleans)

Yes, but the problem is now fixed in the rev 1.06.0 (changelog.txt):

Version 1.06.0
.....
[fixed]
.....
- #797: False-positive warnings when mixing booleans with comparisons in logic operations
.....

But '(n = 5)' always returns an Integer!
See Operator = (Equal)

[sancho2]

1.06 is not yet released though. Is that right?

[fxm]

Yes, but a current version compiled daily (with manual) is available at http://users.freebasic-portal.de/stw/builds/

[Haubitze]

i think this will work without any problems.

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if ( b = TRUE ) and ( n = 5 ) then
...
endif

salute

[xlucas]

Thanks, guys. Yeah, it makes sense that because of how things were in QB and also in FB before Boolean came up, truth in expressions is finally evaluated as an Integer. I like understanding why this happens, not just how to fix it, so thanks again. So if I later want to update FB, which is already installed in my GNU/Linux computer, do I just download the new version and proceed with a normal install? Will it overwrite the old compiler and continue to compile normally?