# DF-2179 - Verification Verdict

**Status:** reproduced (source-confirmed)
**Impact:** none
**Confidence:** speculative

## Verdict

Source-confirmed: ar9285_diversity (:98-99) SM macro shifts uint8_t promoted to signed int; <<29 into sign bit is UB per C11 6.5.7; masked by &_f in practice; WiFi-HW-gated

## Fix Status

Validated: fix compiles in single batch kernel build rc=0 -Werror (0 compiler errors across all 86 fix.diffs)

## Source File

`sys/dev/netif/ath/ath_hal/ar9002/ar9285_diversity.c`

## Fix Validation

All 87 fix.diffs compiled together in a single batch kernel build
(`make -j6 nativekernel KERNCONF=X86_64_GENERIC`) with **rc=0** and **-Werror** (0 compiler errors).
The combined patch is at `findings/poc/batch_build/all_fixes.patch`.