[cfe-dev] "auto *IL = dyn_cast<IntegerLiteral>(e); " IL becomes NULL fails for negative integers.

[Keane, Erich via cfe-dev]

The -100 is not the integer literal for 100 less than 0. It is the application of the unary operator '-' to the integer literal 100.

If you want to get the value, do the overload of isConstantExpr on Expr they takes a reference to APValue.

On Nov 2, 2019 1:16 PM, Devendran Mani via cfe-dev <cfe-dev at lists.llvm.org> wrote:



Hi All,


I need a support to find the below *IL  null pointer return for negative

integer numbers.



Checker code:


const Expr *e = vDecl->getInit();

auto *IL = dyn_cast<IntegerLiteral>(e);


if(IL !=NULL)

{

    double val = IL->getValue().signedRoundToDouble();

    cout << "val:" val;

}


test function:


main()

{

    int val = 100;  (int val = -100;)

    printf("%d", val);

}



if the local variable is positive ex: int var 100;  then cout prints the

right value "100".

But if the local variable is negative ex: int var -100;  then IL becomes

NULL and cout is not executed.


Please help me root cause this issue.


Thanks,

Devendran.



Sent from Yahoo Mail for iPad<https://overview.mail.yahoo.com/?.src=iOS>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20191102/9d09c96c/attachment.html>