diff --git a/plugins/channelrx/demoddatv/ldpctool/generic.h b/plugins/channelrx/demoddatv/ldpctool/generic.h
index 489a36edb..7a6839816 100644
--- a/plugins/channelrx/demoddatv/ldpctool/generic.h
+++ b/plugins/channelrx/demoddatv/ldpctool/generic.h
@@ -327,12 +327,15 @@ struct OffsetMinSumAlgorithm<int8_t, UPDATE, FACTOR>
 	static void finalp(int8_t *links, int cnt)
 	{
 		int8_t beta = std::nearbyint(0.5 * FACTOR);
-		int8_t mags[cnt], mins[cnt];
+		std::vector<int8_t> scratch(3 * cnt);
+		int8_t *mags = scratch.data();
+		int8_t *mins = mags + cnt;
+		int8_t *signs = mins + cnt;
+
 		for (int i = 0; i < cnt; ++i)
 			mags[i] = subu(sqabs(links[i]), beta);
 		CODE::exclusive_reduce(mags, mins, cnt, min);
 
-		int8_t signs[cnt];
 		CODE::exclusive_reduce(links, signs, cnt, xor_);
 		for (int i = 0; i < cnt; ++i)
 			signs[i] |= 127;