8244959: Jextract's VarargsInvoker fails to link functions when passing integer types other than long

src/jdk.incubator.jextract/share/classes/jdk/incubator/jextract/tool/resources/RuntimeHelper.java.template

@@ -165,10 +165,20 @@ public class RuntimeHelper {
             }
         }
 
+        private Class<?> promote(Class<?> c) {
+            if (c == byte.class || c == char.class || c == short.class || c == int.class) {
+                return long.class;
+            } else if (c == float.class) {
+                return double.class;
+            } else {
+                return c;
+            }
+        }
+
         private Class<?> normalize(Class<?> c) {
             c = unboxIfNeeded(c);
             if (c.isPrimitive()) {
-                return c;
+                return promote(c);
             }
             if (MemoryAddress.class.isAssignableFrom(c)) {
                 return MemoryAddress.class;
@@ -180,11 +190,9 @@ public class RuntimeHelper {
         }
 
         private MemoryLayout variadicLayout(Class<?> c) {
-            if (c == char.class || c == byte.class || c == short.class || c == int.class || c == long.class) {
-                //it is ok to approximate with a machine word here; numerics arguments in a prototype-less
-                //function call are always rounded up to a register size anyway.
+            if (c == long.class) {
                 return C_LONGLONG;
-            } else if (c == float.class || c == double.class) {
+            } else if (c == double.class) {
                 return C_DOUBLE;
             } else if (MemoryAddress.class.isAssignableFrom(c)) {
                 return C_POINTER;

test/jdk/tools/jextract/test8244959/Test8244959.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import org.testng.annotations.Test;
+
+import jdk.incubator.foreign.MemorySegment;
+
+import static org.testng.Assert.assertEquals;
+import static test.jextract.printf.Cstring.*;
+import static test.jextract.printf.printf_h.*;
+
+/*
+ * @test
+ * @library ..
+ * @modules jdk.incubator.jextract
+ * @run driver JtregJextract -t test.jextract.printf -- printf.h
+ * @run testng/othervm -Dforeign.restricted=permit Test8244959
+ */
+public class Test8244959 {
+    @Test
+    public void testsPrintf() {
+        try (MemorySegment s = MemorySegment.allocateNative(1024)) {
+            sprintf(s.baseAddress(),
+                toCString("%hhd %c %.2f %.2f %ld %ld %d %hd %d %d %lld %c").baseAddress(),
+                (byte) 1, 'b', -1.25f, 5.5d, -200l, Long.MAX_VALUE, (byte) -2, (short) 2, 3, (short) -4, 5l, 'a');
+            String str = toJavaString(s.baseAddress());
+            assertEquals(str, "1 b -1.25 5.50 -200 " + Long.MAX_VALUE + " -2 2 3 -4 5 a");
+        }
+    }
+}

test/jdk/tools/jextract/test8244959/printf.h

@@ -0,0 +1 @@
+int sprintf(char *buf, const char *fmt, ...);