ImportC: Postfix ++ on a bitfield causes a segfault

[ArthaTi]

Reduced example:

#include <stdint.h>
#include <stdbool.h>

typedef uint16_t TSStateId;
typedef struct {
  TSStateId state;
  uint16_t production_id;
  uint8_t child_index: 7;
  bool done: 1;
} AnalysisSubgraphNode;

int main() {

    AnalysisSubgraphNode successor = {
      .state = 0,
      .child_index = 0,
    };

    successor.child_index++;

}

LDC version:

LDC - the LLVM D compiler (1.39.0):
  based on DMD v2.109.1 and LLVM 18.1.8
  built with LDC - the LLVM D compiler (1.38.0)
  Default target: x86_64-pc-linux-gnu
  Host CPU: znver1