r: Lower optimization level when using Fujitsu compiler@4.1.0. (#15418)

var/spack/repos/builtin/packages/r/change_optflags_tmp.patch

@@ -0,0 +1,67 @@
+diff -ur R-3.6.3.org/configure R-3.6.3/configure
+--- R-3.6.3.org/configure	2020-03-09 11:09:16.060825352 +0900
++++ R-3.6.3/configure	2020-03-09 11:10:47.011280195 +0900
+@@ -6470,13 +6470,13 @@
+   CFLAGS=$ac_save_CFLAGS
+ elif test $ac_cv_prog_cc_g = yes; then
+   if test "$GCC" = yes; then
+-    CFLAGS="-g -O2"
++    CFLAGS="-g -O1"
+   else
+     CFLAGS="-g"
+   fi
+ else
+   if test "$GCC" = yes; then
+-    CFLAGS="-O2"
++    CFLAGS="-O1"
+   else
+     CFLAGS=
+   fi
+@@ -7445,13 +7445,13 @@
+   FCFLAGS=$ac_save_FCFLAGS
+ elif test $ac_cv_prog_fc_g = yes; then
+   if test "x$ac_cv_fc_compiler_gnu" = xyes; then
+-    FCFLAGS="-g -O2"
++    FCFLAGS="-g -O1"
+   else
+     FCFLAGS="-g"
+   fi
+ else
+   if test "x$ac_cv_fc_compiler_gnu" = xyes; then
+-    FCFLAGS="-O2"
++    FCFLAGS="-O1"
+   else
+     FCFLAGS=
+   fi
+@@ -7717,13 +7717,13 @@
+   CXXFLAGS=$ac_save_CXXFLAGS
+ elif test $ac_cv_prog_cxx_g = yes; then
+   if test "$GXX" = yes; then
+-    CXXFLAGS="-g -O2"
++    CXXFLAGS="-g -O1"
+   else
+     CXXFLAGS="-g"
+   fi
+ else
+   if test "$GXX" = yes; then
+-    CXXFLAGS="-O2"
++    CXXFLAGS="-O1"
+   else
+     CXXFLAGS=
+   fi
+@@ -8336,13 +8336,13 @@
+   OBJCFLAGS=$ac_save_OBJCFLAGS
+ elif test $ac_cv_prog_objc_g = yes; then
+   if test "$GOBJC" = yes; then
+-    OBJCFLAGS="-g -O2"
++    OBJCFLAGS="-g -O1"
+   else
+     OBJCFLAGS="-g"
+   fi
+ else
+   if test "$GOBJC" = yes; then
+-    OBJCFLAGS="-O2"
++    OBJCFLAGS="-O1"
+   else
+     OBJCFLAGS=
+   fi

var/spack/repos/builtin/packages/r/package.py

@@ -86,6 +86,12 @@ class R(AutotoolsPackage):
 
     patch('zlib.patch', when='@:3.3.2')
 
+    # R cannot be built with '-O2' optimization
+    # with Fujitsu Compiler @4.1.0 now.
+    # Until the Fujitsu compiler resolves this problem,
+    # temporary fix to lower the optimization level.
+    patch('change_optflags_tmp.patch', when='%fj@4.1.0')
+
     filter_compiler_wrappers(
         'Makeconf', relative_root=os.path.join('rlib', 'R', 'etc')
     )