diff --git a/.github/workflows/build_test.yml b/.github/workflows/build_test.yml
index b6476d7045..a6b14dc235 100644
--- a/.github/workflows/build_test.yml
+++ b/.github/workflows/build_test.yml
@@ -28,8 +28,8 @@ jobs:
           - { COMPILER: "gcc",   COMPILER_VERSION: "11", LINKER: "bfd",  CRYPTOLIB: "gcrypt"  }
           - { COMPILER: "gcc",   COMPILER_VERSION: "13", LINKER: "mold", CRYPTOLIB: "openssl" }
           - { COMPILER: "clang", COMPILER_VERSION: "14", LINKER: "mold", CRYPTOLIB: "gcrypt"  }
-          - { COMPILER: "clang", COMPILER_VERSION: "15", LINKER: "bfd",  CRYPTOLIB: "openssl" }
-          - { COMPILER: "clang", COMPILER_VERSION: "17", LINKER: "lld",  CRYPTOLIB: "auto"    }
+          - { COMPILER: "clang", COMPILER_VERSION: "16", LINKER: "bfd",  CRYPTOLIB: "openssl" }
+          - { COMPILER: "clang", COMPILER_VERSION: "18", LINKER: "lld",  CRYPTOLIB: "auto"    }
     env: ${{ matrix.env }}
     steps:
       - name: Repository checkout