From e300da4db42e2484d98f4982d03150d83436304e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B6nke=20Holz?= <sholz8530@gmail.com>
Date: Sun, 20 Aug 2023 19:46:39 +0200
Subject: [PATCH] AK: Don't use GCC's `__builtin_ffs` on riscv64 without Zbb
 extension

GCC redirects `__builtin_ffs` to `ffs` on RISC-V without the Zbb
extension, causing a linker error.
---
 AK/BuiltinWrappers.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/AK/BuiltinWrappers.h b/AK/BuiltinWrappers.h
index bd0620d1a8..a4a68a83e1 100644
--- a/AK/BuiltinWrappers.h
+++ b/AK/BuiltinWrappers.h
@@ -134,7 +134,7 @@ inline constexpr int count_leading_zeroes_safe(IntType value)
 template<Integral IntType>
 inline constexpr int bit_scan_forward(IntType value)
 {
-#if defined(AK_COMPILER_CLANG) || defined(AK_COMPILER_GCC)
+#if defined(AK_COMPILER_CLANG) || (defined(AK_COMPILER_GCC) && (!ARCH(RISCV64) || defined(__riscv_zbb)))
     static_assert(sizeof(IntType) <= sizeof(unsigned long long));
     if constexpr (sizeof(IntType) <= sizeof(unsigned int))
         return __builtin_ffs(value);