--- configure.ac.orig	2018-01-03 18:12:16 UTC
+++ configure.ac
@@ -2482,7 +2482,7 @@ AS_IF([test "$ac_cv_func_qsort_r" != no]
   AC_CACHE_CHECK(whether qsort_r is GNU version, rb_cv_gnu_qsort_r,
     [AC_TRY_COMPILE([
 @%:@include <stdlib.h>
-void qsort_r(void *base, size_t nmemb, size_t size,
+void (qsort_r)(void *base, size_t nmemb, size_t size,
 	    int (*compar)(const void *, const void *, void *),
 	    void *arg);
 ],[ ],
@@ -2492,7 +2492,7 @@ void qsort_r(void *base, size_t nmemb, s
   AC_CACHE_CHECK(whether qsort_r is BSD version, rb_cv_bsd_qsort_r,
     [AC_TRY_COMPILE([
 @%:@include <stdlib.h>
-void qsort_r(void *base, size_t nmemb, size_t size,
+void (qsort_r)(void *base, size_t nmemb, size_t size,
 	     void *arg, int (*compar)(void *, const void *, const void *));
 ],[ ],
       [rb_cv_bsd_qsort_r=yes],
@@ -3245,7 +3245,7 @@ AS_IF([test "$with_dln_a_out" != yes], [
 			: ${LDSHARED='$(CC) -shared'}
 			AS_IF([test "$rb_cv_binary_elf" = yes], [
 			    LDFLAGS="$LDFLAGS -rdynamic"
-			    DLDFLAGS="$DLDFLAGS "'-Wl,-soname,$@'
+			    DLDFLAGS="$DLDFLAGS "'-Wl,-E'
 			], [
 			  test "$GCC" = yes && test "$rb_cv_prog_gnu_ld" = yes || LDSHARED='$(LD) -Bshareable'
 			])
@@ -3724,6 +3724,7 @@ AS_CASE("$enable_shared", [yes], [
 	SOLIBS='$(LIBS)'
 	LIBRUBY_SO='lib$(RUBY_SO_NAME).$(SOEXT).$(MAJOR)$(MINOR)'
 	LIBRUBY_SONAME='$(LIBRUBY_SO)'
+	RUBY_APPEND_OPTIONS(LIBRUBY_DLDFLAGS, ['-Wl,-soname,${LIBRUBY_SO}'])
 	AS_IF([test "$rb_cv_binary_elf" != "yes" ], [
 	    LIBRUBY_SO="$LIBRUBY_SO.\$(TEENY)"
 	    LIBRUBY_ALIASES=''