Backport upstream fixes for ruby 2.7 (as small as possible for now)

swig-4.0.1-ruby27-minimum.patch

@@ -0,0 +1,11 @@
+--- swig-4.0.1/Lib/ruby/rubytracking.swg.orig	2019-08-21 06:34:03.000000000 +0900
++++ swig-4.0.1/Lib/ruby/rubytracking.swg	2020-01-18 18:32:38.909450596 +0900
+@@ -69,7 +69,7 @@ SWIGRUNTIME void SWIG_RubyInitializeTrac
+     swig_ruby_trackings = (st_table*)NUM2SWIG(trackings_value);
+   }
+ 
+-  rb_define_virtual_variable("SWIG_TRACKINGS_COUNT", swig_ruby_trackings_count, NULL);
++  rb_define_virtual_variable("SWIG_TRACKINGS_COUNT", (rb_gvar_getter_t *)swig_ruby_trackings_count, (rb_gvar_setter_t *)NULL);
+ }
+ 
+ /* Add a Tracking from a C/C++ struct to a Ruby object */

swig.spec

@@ -51,7 +51,7 @@
 Summary: Connects C/C++/Objective C to some high-level programming languages
 Name:    swig
 Version: 4.0.1
-Release: 3%{?dist}
+Release: 4%{?dist}
 License: GPLv3+ and BSD
 URL:     http://swig.sourceforge.net/
 Source0: http://downloads.sourceforge.net/project/swig/swig/swig-%{version}/swig-%{version}.tar.gz
@@ -64,6 +64,10 @@ Source4: ccache-swig.csh
 %endif
 
 Patch0:  swig308-Do-not-use-isystem.patch
+# https://github.com/swig/swig/issues/1689
+# https://github.com/swig/swig/pull/1692/commits/00e291b319bd6b58bf061feee3721a58c9c6be32
+# For now, modify as small as possible for ruby 2.7 build
+Patch1:  swig-4.0.1-ruby27-minimum.patch
 
 BuildRequires: perl-interpreter, pcre-devel
 %if %{python2lang}
@@ -165,6 +169,7 @@ in gdb.
 %setup -q -n swig-%{version}
 
 %patch0 -p1 -b .isystem
+%patch1 -p1 -b .ruby27
 
 for all in CHANGES README; do
     iconv -f ISO88591 -t UTF8 < $all > $all.new
@@ -337,6 +342,9 @@ install -pm 644 Tools/swig.gdb %{buildroot}%{_datadir}/%{name}/gdb
 %{_datadir}/%{name}/gdb
 
 %changelog
+* Sat Jan 18 2020 Mamoru TASAKA <mtasaka@fedoraproject.org> - 4.0.1-4
+- Backport upstream fixes for ruby 2.7 (as small as possible for now)
+
 * Tue Nov 19 2019 Jitka Plesnikova <jplesnik@redhat.com> - 4.0.1-3
 - Disable Ruby tests on all archs