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Questions - bit-fields

C++ bit field member variable initialization value (UE4 example)

I'm wondering what value a bit-field class member variable will have if it is not explicitly initialized. Using an example from unreal engine 4.27: //member variable of UPrimitiveComponent //there are...
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badger5000

c++

initialization

unreal-engine4

bit-fields

Votes: 0

Answers: 1

Latest Answer

Dug a little bit deeper, so I'll try to answer this myself. I believe that for a normal C++ class it would be undefined behaviour as I cannot find any info suggesting otherwise for bit-fields specific...
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badger5000

Avoid volatile bit-field assignment expression reading or writing memory several times

I want to use volatile bit-field struct to set hardware register like following code union foo { uint32_t value; struct { uint32_t x : 1; uint32_t y : 3; uint32_t z : 2...
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old cat

c

assembly

embedded

volatile

bit-fields

Votes: 0

Answers: 3

Latest Answer

I think this is a bug in GCC. Per discussion below, you might consider using: f_ptr->value = (union foo) { .x = 1, .y = 7, .z = 10, } .value; By the C standard, the co...
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Eric Postpischil

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