Port configure script to C99

R-rJava-configure-c99.patch

@@ -0,0 +1,33 @@
+Avoid implicit int in inline keyword check.
+
+This prevents the check from going wrong with future compilers which
+do not support implicit ints.
+
+Submitted upstream: <https://github.com/s-u/rJava/pull/305>
+
+diff --git a/rJava/configure b/rJava/configure
+index 4858bc30fa9610b3..41dd6c9fe27617c8 100755
+--- a/rJava/configure
++++ b/rJava/configure
+@@ -3624,7 +3624,7 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+ /* end confdefs.h.  */
+ 
+ static inline int foo(int a, int b);
+-static f = 1;
++static int f = 1;
+ static inline int foo(int a, int b) { return a+b; }
+ int main(void) {
+     return foo(f,-1);
+diff --git a/rJava/configure.ac b/rJava/configure.ac
+index 79a175f46be77cf7..14090b77b9fb22c5 100644
+--- a/rJava/configure.ac
++++ b/rJava/configure.ac
+@@ -104,7 +104,7 @@ AS_MESSAGE([checking whether ${CC} supports static inline...])
+ can_inline=no
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+ static inline int foo(int a, int b);
+-static f = 1;
++static int f = 1;
+ static inline int foo(int a, int b) { return a+b; }
+ int main(void) {
+     return foo(f,-1);

R-rJava.spec

@@ -10,6 +10,7 @@ Summary:        Low-Level R to Java Interface
 License:        LGPL-2.1-only
 URL:            https://cran.r-project.org/package=%{packname}
 Source0:        %{url}&version=%{packvers}#/%{packname}_%{packvers}.tar.gz
+Patch0:         R-rJava-configure-c99.patch
 
 BuildRequires:  R-devel >= 3.6.0
 Recommends:     %{name}-javadoc = %{version}-%{release}
@@ -29,6 +30,7 @@ Javadoc for %{name}
 
 %prep
 %setup -q -c -n %{packname}
+%patch -P 0 -p1
 rm %{packname}/inst/jri/*.jar
 
 %build