diff --git a/srcpkgs/zimg/patches/fix-size_t.patch b/srcpkgs/zimg/patches/fix-size_t.patch
new file mode 100644
index 00000000000..709e1f4ff7a
--- /dev/null
+++ b/srcpkgs/zimg/patches/fix-size_t.patch
@@ -0,0 +1,50 @@
+--- src/zimg/colorspace/matrix3.cpp	2020-03-02 05:50:02.000000000 +0100
++++ src/zimg/colorspace/matrix3.cpp	2020-08-23 20:46:14.298311898 +0200
+@@ -17,7 +17,7 @@
+ {
+ 	Vector3 ret;
+ 
+-	for (size_t i = 0; i < 3; ++i) {
++	for (std::size_t i = 0; i < 3; ++i) {
+ 		ret[i] = v1[i] * v2[i];
+ 	}
+ 	return ret;
+@@ -27,10 +27,10 @@
+ {
+ 	Vector3 ret;
+ 
+-	for (size_t i = 0; i < 3; ++i) {
++	for (std::size_t i = 0; i < 3; ++i) {
+ 		double accum = 0;
+ 
+-		for (size_t k = 0; k < 3; ++k) {
++		for (std::size_t k = 0; k < 3; ++k) {
+ 			accum += m[i][k] * v[k];
+ 		}
+ 		ret[i] = accum;
+@@ -42,11 +42,11 @@
+ {
+ 	Matrix3x3 ret;
+ 
+-	for (size_t i = 0; i < 3; ++i) {
+-		for (size_t j = 0; j < 3; ++j) {
++	for (std::size_t i = 0; i < 3; ++i) {
++		for (std::size_t j = 0; j < 3; ++j) {
+ 			double accum = 0;
+ 
+-			for (size_t k = 0; k < 3; ++k) {
++			for (std::size_t k = 0; k < 3; ++k) {
+ 				accum += a[i][k] * b[k][j];
+ 			}
+ 			ret[i][j] = accum;
+@@ -98,8 +98,8 @@
+ {
+ 	Matrix3x3 ret;
+ 
+-	for (size_t i = 0; i < 3; ++i) {
+-		for (size_t j = 0; j < 3; ++j) {
++	for (std::size_t i = 0; i < 3; ++i) {
++		for (std::size_t j = 0; j < 3; ++j) {
+ 			ret[i][j] = m[j][i];
+ 		}
+ 	}