diff --git a/srcpkgs/avogadro/patches/glibc.patch b/srcpkgs/avogadro/patches/glibc.patch
new file mode 100644
index 0000000000..4d652af22c
--- /dev/null
+++ b/srcpkgs/avogadro/patches/glibc.patch
@@ -0,0 +1,18 @@
+--- libavogadro/src/extensions/symmetry/libmsym/src/orbital.c.orig
++++ libavogadro/src/extensions/symmetry/libmsym/src/orbital.c
+@@ -67,13 +67,13 @@
+         }
+         case 2 : {
+             //o->v = dpolynomial[m+l];
+-            char *d = (signbit(m) == 1 ? "-" : "+");
++            char *d = (signbit(m*1.0) == 1 ? "-" : "+");
+             snprintf(o->name, sizeof(o->name), "%dd%d%s",n,abs(m),d);
+             break;
+         }
+         default : {
+             char t = 'f' - 3 + l;
+-            char *d = (signbit(m) == 1 ? "-" : "+");
++            char *d = (signbit(m*1.0) == 1 ? "-" : "+");
+             snprintf(o->name, sizeof(o->name), "%d%c%d%s",n,t,abs(m),d);
+         }
+     }
diff --git a/srcpkgs/avogadro/template b/srcpkgs/avogadro/template
index 5fb643ca45..6e0e552ad2 100644
--- a/srcpkgs/avogadro/template
+++ b/srcpkgs/avogadro/template
@@ -14,6 +14,9 @@ homepage="http://avogadro.cc"
 distfiles="https://github.com/cryos/avogadro/archive/${version}.tar.gz"
 checksum=6453e36e8ae3e61655cbe062df6d6fa6b2409122c7b5abc0a6f1d410a181640b
 
+pre_build() {
+	sed -i 's|_BSD_SOURCE|_DEFAULT_SOURCE|g' CMakeLists.txt
+}
 post_install() {
 	rm -rf ${DESTDIR}/usr/features
 }