From e1ac2e0cfb2e9eebeb87ec6550fe44ff2990d7f9 Mon Sep 17 00:00:00 2001
From: James Eapen <james.eapen@vai.org>
Date: Mon, 2 Dec 2024 11:33:59 -0500
Subject: [PATCH] docs(README): note about GNU GCC on macos

---
 README.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/README.md b/README.md
index b08ce21..bcca38f 100644
--- a/README.md
+++ b/README.md
@@ -42,6 +42,16 @@ with `pkg-config`:
 pkg-config --cflags --libs htslib
 ```
 
+#### GCC
+
+GNU GCC must be installed for OpenMP support. This is usually installed by
+default on Linux systems, but may need to be manually installed on MacOS to be
+able to use iscream with multiple threads[^1].
+
+[^1]: Using OpenMP is also possible with Clang on MacOS
+(<https://mac.r-project.org/openmp/>) but installing GCC with Homebrew may be
+easier (<https://formulae.brew.sh/formula/gcc>).
+
 ### GitHub
 
 You can install the development version from Github by cloning the repo and