diff --git a/recipes-musicians/guitarix/guitarix.bb b/recipes-musicians/guitarix/guitarix.bb
index 32ccc8d..1ec3975 100644
--- a/recipes-musicians/guitarix/guitarix.bb
+++ b/recipes-musicians/guitarix/guitarix.bb
@@ -7,6 +7,7 @@ PV = "0.38.0"
 SRC_URI = " \
     ${SOURCEFORGE_MIRROR}/project/${BPN}/${BPN}/${BPN}2-${PV}.tar.xz \
     file://0001-do-not-perform-link-test-durin-cross-build.patch \
+    file://0002-Fix-build-for-musl.patch \
 "
 SRC_URI[md5sum] = "c533bfd7223c42a7aef0e516f5b4cc01"
 SRC_URI[sha256sum] = "c709ec903b2ae653802bd9327c32a20a086e6a97e8d029c8d79f1a8445dd655b"
diff --git a/recipes-musicians/guitarix/guitarix/0002-Fix-build-for-musl.patch b/recipes-musicians/guitarix/guitarix/0002-Fix-build-for-musl.patch
new file mode 100644
index 0000000..a361dd4
--- /dev/null
+++ b/recipes-musicians/guitarix/guitarix/0002-Fix-build-for-musl.patch
@@ -0,0 +1,38 @@
+From 2e98159fe860cb42458fa3b434fe0eacda5e4b97 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Andreas=20M=C3=BCller?= <schnitzeltony@gmail.com>
+Date: Sun, 7 Apr 2019 20:56:49 +0200
+Subject: [PATCH] Fix build for musl
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+The function mallopt and it's constants doe not seem to be defined by POSIX so
+musl does not define them. Get around by check for constants.
+
+Upstream-Status: Applied [1]
+
+[1] https://sourceforge.net/p/guitarix/git/ci/8ec1f3088e914e87cf2c04764b24e2bd5cafc940/
+
+Signed-off-by: Andreas Müller <schnitzeltony@gmail.com>
+---
+ src/gx_head/gui/machine.cpp | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/src/gx_head/gui/machine.cpp b/src/gx_head/gui/machine.cpp
+index bdc137d..d912839 100644
+--- a/src/gx_head/gui/machine.cpp
++++ b/src/gx_head/gui/machine.cpp
+@@ -35,8 +35,10 @@
+ void set_memory_allocation() {
+     if (mlockall(MCL_CURRENT | MCL_FUTURE))
+         gx_print_error("system init", "mlockall failed:");
++#if defined(M_TRIM_THRESHOLD) && defined(M_MMAP_MAX)
+     mallopt(M_TRIM_THRESHOLD, -1);
+     mallopt(M_MMAP_MAX, 0);
++#endif
+ }
+ 
+ #else
+-- 
+2.20.1
+