diff --git a/common/include/villas/utils.hpp b/common/include/villas/utils.hpp
index db8d22f4a..771aa9c12 100644
--- a/common/include/villas/utils.hpp
+++ b/common/include/villas/utils.hpp
@@ -82,7 +82,7 @@
 #define CEIL(x, y)	(((x) + (y) - 1) / (y))
 
 /** Get nearest up-rounded power of 2 */
-#define LOG2_CEIL(x)	(1 << (log2i((x) - 1) + 1))
+#define LOG2_CEIL(x)	(1 << (villas::utils::log2i((x) - 1) + 1))
 
 /** Check if the number is a power of 2 */
 #define IS_POW2(x)	(((x) != 0) && !((x) & ((x) - 1)))
@@ -186,12 +186,7 @@ void * memdup(const void *src, size_t bytes);
 void die();
 
 /** Get log2 of long long integers */
-static inline int log2i(long long x) {
-	if (x == 0)
-		return 1;
-
-	return sizeof(x) * 8 - __builtin_clzll(x) - 1;
-}
+int log2i(long long x);
 
 /** Send signal \p sig to main thread. */
 void killme(int sig);
diff --git a/common/lib/utils.cpp b/common/lib/utils.cpp
index 0057fa5a0..39e7d3b48 100644
--- a/common/lib/utils.cpp
+++ b/common/lib/utils.cpp
@@ -331,6 +331,13 @@ size_t strlenp(const char *str)
 	return sz;
 }
 
+int log2i(long long x) {
+	if (x == 0)
+		return 1;
+
+	return sizeof(x) * 8 - __builtin_clzll(x) - 1;
+}
+
 int sha1sum(FILE *f, unsigned char *sha1)
 {
 	SHA_CTX c;