Undeclared variable from base class when derived class has property

I have the following code below, where a base class has a member which is (should be) accessible by a derived class.

The code below however gives a compilation error ...abcAppDelegate.m:30: error: 'baseVal_' undeclared (first use in this function)

If I call the variable using self->baseVal_ or if I remove the property defined in the derived class then everything is ok.

Also, if I define a category of the derived class, then I can access baseVal_ without error.


@interface BaseClass : NSObject 
    BOOL baseVal_;

@implementation BaseClass 


@interface DerivedClass : BaseClass {
@property (readwrite) BOOL val;

@implementation DerivedClass
@synthesize val;
- (void) foo {
    baseVal_ = YES;


Have a look here: Click. Seems to possibly be a bug with GCC, but it's easily fixable by adding val as an instance variable instead of using the property without.

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