Update to Xcode 6.3 breaks app - Google GTLTouchStaticLib "not equal to a null pointer is always true"

Question

I use Google Drive SDK in my app.

It has worked perfectly since around June 2014.

Following update to Xcode 6.3, none of my targets build.

The implementation file GTMOAuth2ViewControllerTouch.m contains two blocks that the compiler complains about:

if (accessibility == NULL && &kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly != NULL) { accessibility = kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly; }

specifically with the message: "Comparison of address of kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly not equal to a null pointer is always true".

AND

if (accessibility != NULL && &kSecAttrAccessible != NULL) { [keychainQuery setObject:(id)accessibility forKey:(id)kSecAttrAccessible]; }

specifically with the message: "Comparison of address of kSecAttrAccessible not equal to a null pointer is always true".

The compiler is telling me that the two keys when compared to != NULL is always true.

I believe my lack of computer science training leaves me unable to understand the issue here - maybe that is just a bad perception?

I've had a look at this question but cannot understand the context in relation to my problem with Google Drive SDK implementation file GTMOAuth2ViewControllerTouch.m

I'd really like to understand the underlying issue.

Please help...

Schemetrical · Accepted Answer · 2015-04-11 05:12:31Z

7

Instead of those snippets, you can use: accessibility = kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly; and [keychainQuery setObject:(id)accessibility forKey:(id)kSecAttrAccessible];

This is because the constants will never have a NULL pointer, so there is no reason to do checking. I believe an update to the SDK is available to fix but you can do it manually.

answered Apr 11, 2015 at 5:12

Schemetrical

5,5162 gold badges28 silver badges43 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

andrewbuilder Over a year ago

Appreciate your prompt assistance @Schemetrical. All targets build with your suggested changes - thank you. Wish I had thought to check the Google SDK, but ended doing the changes manually as you've written.

andrewbuilder Over a year ago

Are you able to explain why this changed between Xcode 6.2 / iOS 8.2 & Xcode 6.3 / iOS 8.3?

Schemetrical Over a year ago

I believe the code was there to check if the constant existed. In 6.3, Xcode now checks the iOS version you use and the static analyser will spew errors for unnecessary code (such as comparing something to nothing always false).

dgatwood · Accepted Answer · 2015-07-13 22:15:54Z

Apple added a new check to their compiler that warn when these checks can never fail, but unfortunately, it does so based on the current deployment target. For those of us who share code between projects with multiple deployment targets, though, that new feature is a real headache.

I'm told that you can disable the warning globally by adding -Wno-tautological-pointer-compare to your compiler flags, or on a one-off basis by wrapping the "&whatever" in parentheses.

Collectives™ on Stack Overflow

Update to Xcode 6.3 breaks app - Google GTLTouchStaticLib "not equal to a null pointer is always true"

2 Answers 2

3 Comments

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Linked

Related