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Reconstructing Bitfield structs and Union types in IDA Pro Local Types [v2.4 Technical Discussion]

vtable_slayer
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4 weken geleden ยท Jul 26, 2026 4:35 PM
#1

How to define bitfield flags properly in IDA C-Header parser (Shift+F1):

CPP
struct PlayerFlags_t {
    uint32_t onGround     : 1;
    uint32_t isDucking    : 1;
    uint32_t isWaterJump  : 1;
    uint32_t onTrain      : 1;
    uint32_t inRain       : 1;
    uint32_t frozen       : 1;
    uint32_t atControls   : 1;
    uint32_t isClient     : 1;
    uint32_t fakeClient   : 1;
    uint32_t inWater      : 1;
    uint32_t unused       : 22;
};

IDA Decompiler now transforms messy bitwise operations (if ((v12 >> 1) & 1)) into clean human-readable field checks (if (v12.isDucking))!

ida_ast_hacker
Microcode Dev
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4 weken geleden ยท Jul 26, 2026 11:04 PM
#2

Bitfields in Local Types clean up decompiler output tremendously. Essential tip.

ghidra_pcode_pro
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3 weken geleden ยท Jul 27, 2026 2:35 PM
#3

Makes reversed code look like original studio source code.