Add check whether Ruby requires explicit specification of C++ standard.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>
(cherry picked from commit 8301a3c8e542675e9b5f310d79ad24b9a12baaf8)

7 files changed, 76 insertions, 4 deletions

diff --git a/korundum/bin/Makefile.am b/korundum/bin/Makefile.am
index 01d89533..72212f5b 100644
--- a/korundum/bin/Makefile.am
+++ b/korundum/bin/Makefile.am
@@ -1,3 +1,5 @@
+CXXFLAGS += $(RUBY_CXXFLAGS)
+
 INCLUDES = $(all_includes) -I$(RUBY_ARCHDIR) $(RUBY_CFLAGS)
 
 bin_PROGRAMS = krubyinit
diff --git a/korundum/rubylib/korundum/configure.in.in b/korundum/configure.in.in
index 0a987639..c420adc9 100644
--- a/korundum/rubylib/korundum/configure.in.in
+++ b/korundum/configure.in.in
@@ -32,6 +32,37 @@ else
      RUBY_CFLAGS="-I${RUBY_INCLUDEDIR}"
   fi
 
+  # check if Ruby requires explicit specification of C++ standard
+  AC_LANG_SAVE
+  AC_LANG_CPLUSPLUS
+  SAVED_CXXFLAGS="$CXXFLAGS"
+  for CXX_STD_TEST in "" 11 14 17; do
+    CXXFLAGS="$SAVED_CXXFLAGS"
+    if test "x$CXX_STD_TEST" = "x"; then
+      AC_MSG_CHECKING([Ruby build with default C++ standard])
+      RUBY_CXXFLAGS=""
+    else
+      AC_MSG_CHECKING([Ruby build with C++$CXX_STD_TEST])
+      RUBY_CXXFLAGS="-std=c++$CXX_STD_TEST"
+    fi
+    CXXFLAGS="$SAVED_CXXFLAGS $RUBY_CFLAGS $RUBY_CXXFLAGS"
+    AC_TRY_COMPILE([
+        #include <ruby.h>
+      ],[ ],
+      ruby_cxx_std=yes,
+      ruby_cxx_std=no
+    )
+    if test "x$ruby_cxx_std" = "xyes"; then
+      AC_SUBST(RUBY_CXXFLAGS)
+      AC_MSG_RESULT(yes)
+      break
+    else
+      AC_MSG_RESULT(no)
+    fi
+  done
+  CXXFLAGS="$SAVED_CXXFLAGS"
+  AC_LANG_RESTORE
+
   # Removes trailing slashes, if any, to avoid fail to install with recent libtool.
   RUBY_ARCHDIR=${RUBY_ARCHDIR%/}
   RUBY_SITEDIR=${RUBY_SITEDIR%/}
@@ -46,7 +77,8 @@ else
                   libdir $RUBY_LIBDIR,
                   includedir $RUBY_INCLUDEDIR,
                   librubyarg $RUBY_LIBRUBYARG,
-                  cflags $RUBY_CFLAGS])
+                  cflags $RUBY_CFLAGS,
+                  cxxflags $RUBY_CXXFLAGS])
   AC_SUBST(RUBY_ARCHDIR)
   AC_SUBST(RUBY_SITEARCHDIR)
   AC_SUBST(RUBY_SITEDIR)
@@ -56,4 +88,3 @@ else
   AC_SUBST(RUBY_LIBRUBYARG)
   AC_SUBST(RUBY_CFLAGS)
 fi
-
diff --git a/korundum/rubylib/korundum/Makefile.am b/korundum/rubylib/korundum/Makefile.am
index 453718b4..568479a5 100644
--- a/korundum/rubylib/korundum/Makefile.am
+++ b/korundum/rubylib/korundum/Makefile.am
@@ -1,3 +1,5 @@
+CXXFLAGS += $(RUBY_CXXFLAGS)
+
 INCLUDES = -I$(top_srcdir)/smoke -I$(top_srcdir)/qtruby/rubylib/qtruby $(all_includes) -I$(RUBY_ARCHDIR) $(RUBY_CFLAGS)
 
 rubylibdir = $(RUBY_ARCHDIR)
diff --git a/qtruby/bin/Makefile.am b/qtruby/bin/Makefile.am
index ac39aeb2..46159ec4 100644
--- a/qtruby/bin/Makefile.am
+++ b/qtruby/bin/Makefile.am
@@ -1,3 +1,5 @@
+CXXFLAGS += $(RUBY_CXXFLAGS)
+
 INCLUDES = $(all_includes) -I$(RUBY_ARCHDIR) $(RUBY_CFLAGS)
 
 bin_PROGRAMS = qtrubyinit
diff --git a/qtruby/rubylib/qtruby/configure.in.in b/qtruby/configure.in.in
index db0594a3..84ad88ec 100644
--- a/qtruby/rubylib/qtruby/configure.in.in
+++ b/qtruby/configure.in.in
@@ -32,6 +32,37 @@ else
      RUBY_CFLAGS="-I${RUBY_INCLUDEDIR}"
   fi
 
+  # check if Ruby requires explicit specification of C++ standard
+  AC_LANG_SAVE
+  AC_LANG_CPLUSPLUS
+  SAVED_CXXFLAGS="$CXXFLAGS"
+  for CXX_STD_TEST in "" 11 14 17; do
+    CXXFLAGS="$SAVED_CXXFLAGS"
+    if test "x$CXX_STD_TEST" = "x"; then
+      AC_MSG_CHECKING([Ruby build with default C++ standard])
+      RUBY_CXXFLAGS=""
+    else
+      AC_MSG_CHECKING([Ruby build with C++$CXX_STD_TEST])
+      RUBY_CXXFLAGS="-std=c++$CXX_STD_TEST"
+    fi
+    CXXFLAGS="$SAVED_CXXFLAGS $RUBY_CFLAGS $RUBY_CXXFLAGS"
+    AC_TRY_COMPILE([
+        #include <ruby.h>
+      ],[ ],
+      ruby_cxx_std=yes,
+      ruby_cxx_std=no
+    )
+    if test "x$ruby_cxx_std" = "xyes"; then
+      AC_SUBST(RUBY_CXXFLAGS)
+      AC_MSG_RESULT(yes)
+      break
+    else
+      AC_MSG_RESULT(no)
+    fi
+  done
+  CXXFLAGS="$SAVED_CXXFLAGS"
+  AC_LANG_RESTORE
+
   # Removes trailing slashes, if any, to avoid fail to install with recent libtool.
   RUBY_ARCHDIR=${RUBY_ARCHDIR%/}
   RUBY_SITEDIR=${RUBY_SITEDIR%/}
@@ -46,7 +77,8 @@ else
                   libdir $RUBY_LIBDIR,
                   includedir $RUBY_INCLUDEDIR,
                   librubyarg $RUBY_LIBRUBYARG,
-                  cflags $RUBY_CFLAGS])
+                  cflags $RUBY_CFLAGS,
+                  cxxflags $RUBY_CXXFLAGS])
   AC_SUBST(RUBY_ARCHDIR)
   AC_SUBST(RUBY_SITEARCHDIR)
   AC_SUBST(RUBY_SITEDIR)
@@ -56,4 +88,3 @@ else
   AC_SUBST(RUBY_LIBRUBYARG)
   AC_SUBST(RUBY_CFLAGS)
 fi
-
diff --git a/qtruby/rubylib/designer/uilib/Makefile.am b/qtruby/rubylib/designer/uilib/Makefile.am
index b7cc229a..c499269a 100644
--- a/qtruby/rubylib/designer/uilib/Makefile.am
+++ b/qtruby/rubylib/designer/uilib/Makefile.am
@@ -1,3 +1,5 @@
+CXXFLAGS += $(RUBY_CXXFLAGS)
+
 INCLUDES = -I$(top_srcdir)/smoke -I$(top_srcdir)/qtruby/rubylib/qtruby $(all_includes) -I$(RUBY_ARCHDIR) $(RUBY_CFLAGS)
 
 rubylibdir = $(RUBY_ARCHDIR)
diff --git a/qtruby/rubylib/qtruby/Makefile.am b/qtruby/rubylib/qtruby/Makefile.am
index 09ac6b0a..2bd1f653 100644
--- a/qtruby/rubylib/qtruby/Makefile.am
+++ b/qtruby/rubylib/qtruby/Makefile.am
@@ -1,3 +1,5 @@
+CXXFLAGS += $(RUBY_CXXFLAGS)
+
 INCLUDES = -I$(top_srcdir)/smoke $(all_includes) -I$(RUBY_ARCHDIR) $(RUBY_CFLAGS)
 
 noinst_HEADERS = qtruby.h marshall.h smokeruby.h extconf.rb