[sdcc-devel] [ sdcc-Bugs-2942343 ] Initialization of non-constant arrays broken.

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Bugs item #2942343, was opened at 2010-01-29 08:25
Message generated for change (Comment added) made by spth
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Category: Icode generator
Group: fixed
Status: Closed
Resolution: Fixed
Priority: 3
Private: No
Submitted By: Philipp Klaus Krause (spth)
Assigned to: Maarten Brock (maartenbrock)
Summary: Initialization of non-constant arrays broken.

Initial Comment:
Initialization of arrays which are not constant is currently borken. The values are not chekced for range or converted to the target type:

const unsigned char x[3] = {255, 256, 257};

gives a warning about out-of-range values.

unsigned char x[3] = {255, 256, 257};

does not.

const _Bool foo[4] = {1, 2, 3, 4};

creates an array of 4 _Bools which all have the value true.

_Bool foo[4] = {1, 2, 3, 4};

creates an array which contains the value true in foo[0], but has the rest of the array initialized by 2,3,4, which are invalid values for _Bool.

Philipp


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>Comment By: Philipp Klaus Krause (spth)
Date: 2012-01-14 05:08

Message:
We didn't even have _Bool back then. I've seen the check uses IS_BOOLEAN,
which is true for __bit and __sbit as well as _Bool. IMO we probably should
do the check for _Bool; I don't know __bit and __sbit.

Philipp


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Comment By: Maarten Brock (maartenbrock)
Date: 2012-01-14 05:02

Message:
The function checkConstantRange() was introduced with this exception by
Bernhard Held in #4206. I have no idea why.

In the meantime Jan Waclawek responded on the developer mailing list with:

> I'd say, if unsigned char a = 256 warns, so should _Bool b = 4.
> 
> I'd also say, unsigned char a = -128 should warn, too.

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Comment By: Philipp Klaus Krause (spth)
Date: 2012-01-14 02:45

Message:
I wonder why there was/is special treatment for _Bool. I'll have a look at
it later.

Philipp


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Comment By: Maarten Brock (maartenbrock)
Date: 2012-01-14 02:17

Message:
Fixed in SDCC 3.1.2 #7216.
Warning for _Bool is still suppressed in checkConstantRange() in SDCCval.c.

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Comment By: Maarten Brock (maartenbrock)
Date: 2012-01-11 15:34

Message:
Philipp and others,

I know how to add the warning. But first I have a question since the
current code does not warn for _Bool with or without const. This is
explicitly coded at present. Do we want a warning for these?

_Bool b = 4;
b = 5;

Maarten

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Comment By: Philipp Klaus Krause (spth)
Date: 2010-09-19 10:49

Message:
I just tried in sdcc 2.9.7 #5983. The bug is partially fixed: The array of
_Bool is initialized to the correct values.

However the warning about out of range values is till missing for the
non-const arrays of all types.

Philipp


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Comment By: Maarten Brock (maartenbrock)
Date: 2010-09-19 07:56

Message:
Philipp,
Can you please recheck this?
SDCC #5982 seems to have this fixed.

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