What will be the value of uninitialized variable? [duplicate]

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Technically, the value of an uninitialized non static local variable is Indeterminate[Ref 1].
In short it can be anything. Accessing such a uninitialized variable leads to an Undefined Behavior.[Ref 2]

[Ref 1]
C99 section 6.7.8 Initialization:

If an object that has automatic storage duration is not initialized explicitly, its value is indeterminate.

[Ref 2]

C99 section 3.18 Undeļ¬ned behavior:

behavior, upon use of a nonportable or erroneous program construct, of erroneous data, or of indeterminately valued objects, for which this International Standard imposes no requirements.

Note: Emphasis mine.

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