Suggest parentheses around '&&' within '||' [-Werror=parentheses]

Using Arduino Programming Questions
1

Hi everyone.
The line got error of: suggest parentheses around '&&' within '||' [-Werror=parentheses]

if(batteryVoltage < 3.78 && batteryVoltage || antiFlicker == 3 )

modified as below eliminated the error.

if(((batteryVoltage < 3.78) && batteryVoltage) || antiFlicker == 3 )

Will the modification effect the correctness of the sketch?
Thanks
Adam

2

The main reason you would do it is for absolute clarity about the order of the operations that you want.

Without the parentheses you need to understand the order of precedence that each of the operations has.

https://en.cppreference.com/w/cpp/language/operator_precedence

2 Likes
3

Great!
Thank you.

4

You ar comparing batteryVoltage to a float and then treat it as a bool.
In that second occurrence, any other value than 0.00000 will evaluate to true.
It is not good practice to compare a float to an exact number.
Consider batteryVoltage > 0.01.

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5

It is not an error but warning that is turned into error with -Werror flag. Makes sense if you are a big company and don’t want someone commit the code that has warnings, are you a big company?

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6

What difference does that make? It's always a best practice to eliminate all warnings.

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7

Does one have to prevent code compiling in order to get rid of warnings?

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8

Write the code so it compiles without warnings.

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9

You haven’t answered my question, I’ll answer it for you - NO.

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10

Question made no sense, so I didn't bother to address it.

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11

Thanks.

12

thanks.
not company.
how to remove -Werror flag?

13

what platform/software are you compiling on

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14

Because warnings are informative, errors are blockers. making warnings blockers is authoritarian unless you did it to yourself. The whole philosophy of C++ is let the user screw up on their own accord and herein lies freedom. If one wants holding hands language they can switch

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15

Thanks for the expanded explanation of your point. I generally agree.

My initial read was that you were advocating not fixing code to eliminate warnings.

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16

Arduino IDE 1.8.19
thanks

17

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