[build] use ccache

1 files changed, 27 insertions, 0 deletions

diff --git a/scripts/set_compiler.sh b/scripts/set_compiler.sh
new file mode 100755
index 0000000000..161126f044
--- /dev/null
+++ b/scripts/set_compiler.sh
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+if [ ! -z "${_CXX}" ]; then export CXX="${_CXX}" ; fi
+if [ ! -z "${_CC}" ]; then export CC="${_CC}" ; fi
+
+if [ "${CCACHE:-0}" -ge 1 ]; then
+    export CXX="ccache ${CXX}"
+    export CC="ccache ${CC}"
+
+    # ccache splits up the compile steps, so we end up with unused arguments in some steps.
+    # Clang also thinks that ccache isn't interactive, so we explicitly need to enable color.
+    if [ $(echo | ${CXX} -dM -E - | grep -c "#define __clang__ 1") -ge 1 ]; then
+        export CXX="${CXX} -Qunused-arguments -fcolor-diagnostics"
+        export CC="${CC} -Qunused-arguments -fcolor-diagnostics"
+    else
+        # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60304
+        # GCC normally throws this error which is in GTest, but *only* when compilation and
+        # preprocessing aren't combined in one step. However, when using ccache with GCC, we are
+        # running them in separate steps, so this warning/error is shown.
+        export CXX="${CXX} -Wno-conversion-null"
+        export CC="${CC} -Wno-conversion-null"
+    fi
+fi
+
+echo "export CXX=\"${CXX}\""
+echo "export CC=\"${CC}\""
+${CXX} --version