diff --git a/.travis.yml b/.travis.yml
index 6b00185..5d4f816 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,13 @@
 language: c
-sudo: required
-dist: bionic
+
 compiler:
 - gcc
 - clang
+
 os:
 - linux
+- osx
+dist: bionic
+osx_image: xcode9.4
+
 script: cmake -H. -Bbuild && cmake --build build
diff --git a/math/vec2f.h b/math/vec2f.h
index d09d79a..f01a37a 100644
--- a/math/vec2f.h
+++ b/math/vec2f.h
@@ -5,25 +5,25 @@ typedef struct vec2f {
   float y;
 } vec2f;
 
-inline vec2f mulf_v2f(float s, vec2f v) {
+static inline vec2f mulf_v2f(float s, vec2f v) {
   v.x *= s;
   v.y *= s;
   return v;
 }
 
-inline vec2f add_v2f(vec2f a, vec2f b) {
+static inline vec2f add_v2f(vec2f a, vec2f b) {
   a.x += b.x;
   a.y += b.y;
   return a;
 }
 
-inline vec2f sub_v2f(vec2f a, vec2f b) {
+static inline vec2f sub_v2f(vec2f a, vec2f b) {
   a.x -= b.x;
   a.y -= b.y;
   return a;
 }
 
-inline vec2f make_v2f(float x, float y) {
+static inline vec2f make_v2f(float x, float y) {
   vec2f v = {x, y};
   return v;
 }
diff --git a/misc/cmp.h b/misc/cmp.h
index 40a1014..792ea43 100644
--- a/misc/cmp.h
+++ b/misc/cmp.h
@@ -2,22 +2,22 @@
 
 #include <stdint.h>
 
-inline float min_f(float a, float b) {
+static inline float min_f(float a, float b) {
   return a < b ? a : b;
 }
 
-inline float max_f(float a, float b) {
+static inline float max_f(float a, float b) {
   return a < b ? b : a;
 }
 
-inline int min_i(int a, int b) {
+static inline int min_i(int a, int b) {
   return a < b ? a : b;
 }
 
-inline int max_i(int a, int b) {
+static inline int max_i(int a, int b) {
   return a < b ? b : a;
 }
 
-inline uint8_t min_u8(uint8_t a, uint8_t b) {
+static inline uint8_t min_u8(uint8_t a, uint8_t b) {
   return a < b ? a : b;
 }