thodg/libgit2

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 7d00f0e..5f1ee19 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -61,6 +61,7 @@ jobs:
           cmake_options: -DUSE_HTTPS=OpenSSL -DREGEX_BACKEND=builtin -DDEPRECATE_HARD=ON -DUSE_LEAK_CHECKER=valgrind -DUSE_GSSAPI=ON
         -
           os: macos-latest
+          cc: gcc
         -
           os: windows-latest
       fail-fast: false