Honor CXX / CC flags when testing R

Author: hcho3

R-package/configure

@@ -2239,12 +2239,18 @@ if test -z "${R_HOME}"; then
   exit 1
 fi
 
-CXX17=`"${R_HOME}/bin/R" CMD config CXX17`
-CXX17STD=`"${R_HOME}/bin/R" CMD config CXX17STD`
-CXX="${CXX17} ${CXX17STD}"
+if [ -z "${CXX:-}" ]
+then
+  CXX17=`"${R_HOME}/bin/R" CMD config CXX17`
+  CXX17STD=`"${R_HOME}/bin/R" CMD config CXX17STD`
+  CXX="${CXX17} ${CXX17STD}"
+fi
 CXXFLAGS=`"${R_HOME}/bin/R" CMD config CXXFLAGS`
 
-CC=`"${R_HOME}/bin/R" CMD config CC`
+if [ -z "${CC:-}" ]
+then
+  CC=`"${R_HOME}/bin/R" CMD config CC`
+fi
 CFLAGS=`"${R_HOME}/bin/R" CMD config CFLAGS`
 CPPFLAGS=`"${R_HOME}/bin/R" CMD config CPPFLAGS`
 

R-package/configure.ac

@@ -10,12 +10,18 @@ if test -z "${R_HOME}"; then
   exit 1
 fi
 
-CXX17=`"${R_HOME}/bin/R" CMD config CXX17`
-CXX17STD=`"${R_HOME}/bin/R" CMD config CXX17STD`
-CXX="${CXX17} ${CXX17STD}"
+if [[ -z "${CXX:-}" ]]
+then
+  CXX17=`"${R_HOME}/bin/R" CMD config CXX17`
+  CXX17STD=`"${R_HOME}/bin/R" CMD config CXX17STD`
+  CXX="${CXX17} ${CXX17STD}"
+fi
 CXXFLAGS=`"${R_HOME}/bin/R" CMD config CXXFLAGS`
 
-CC=`"${R_HOME}/bin/R" CMD config CC`
+if [[ -z "${CC:-}" ]]
+then
+  CC=`"${R_HOME}/bin/R" CMD config CC`
+fi
 CFLAGS=`"${R_HOME}/bin/R" CMD config CFLAGS`
 CPPFLAGS=`"${R_HOME}/bin/R" CMD config CPPFLAGS`
 

ops/pipeline/test-rpkg-impl.sh

@@ -15,5 +15,11 @@ shift 1
 source /opt/miniforge/bin/activate
 
 set -x
+
+mkdir -p ~/.R/
+touch ~/.R/Makevars
+echo "CXX=$CXX" >> ~/.R/Makevars
+echo "CC=$CC" >> ~/.R/Makevars
+
 R -e 'dir.create(Sys.getenv("R_LIBS_USER"), recursive = TRUE)'
 python3 ops/script/test_r_package.py --build-tool="${build_tool}"