981006-1.c: New test.

* special/981006-1.c: New test.  Make sure gcc doesn't lose track of the
possible targets of tablejump insns.
* special/special.exp: Run it.

From-SVN: r22899

gcc/testsuite/gcc.c-torture/ChangeLog

+1998-10-06  Ken Raeburn  <raeburn@cygnus.com>
+
+	* special/981006-1.c: New test.  Make sure gcc doesn't lose track
+	of the possible targets of tablejump insns.
+	* special/special.exp: Run it.
+
 Thu Oct  1 17:15:26 1998  Nick Clifton  <nickc@cygnus.com>
 
 	* compile/981001-1.c: New test.

gcc/testsuite/gcc.c-torture/special/981006-1.c

+/* Test that tablejump insns are correctly handled.  If the compiler
+   loses track of the jump targets, it will report that x and y can be
+   used uninitialized.
+
+   This is broken in egcs 1998/10/06 for mips in pic mode.  */
+/* { dg-do compile } */
+
+int foo (int a, int b)
+{
+  __label__ z;
+  int x; /* { dg-bogus "warning: `.' might be used uninitialized in this function" } */
+  int y; /* { dg-bogus "warning: `.' might be used uninitialized in this function" } */
+  static void *p;
+
+  switch (a) {
+  case 2:
+    x = 4;
+    break;
+  case 4:
+    x = 6;
+    break;
+  case 8: case 10: case 13: case 11: case 17: case 19:
+    x = 7;
+    break;
+  default:
+    x = -1;
+    break;
+  }
+  switch (b) {
+  case 2:
+    y = 4;
+    break;
+  case 4:
+    y = 6;
+    break;
+  case 8: case 10: case 13: case 11: case 17: case 19:
+    y = 7;
+    break;
+  default:
+    y = -1;
+    break;
+  }
+ z:
+  p = &&z;
+  return x * y;
+}
+int main (int argc, char *argv[])
+{
+  return 1 == foo (argc, argc + 1);
+}

gcc/testsuite/gcc.c-torture/special/special.exp

@@ -34,6 +34,20 @@ load_lib gcc-dg.exp
 
 ################## ADD NEXT CASE HERE (NOT AT THE END) ##################
 
+# 981006-1
+# For MIPS at least, pic is needed to trigger the problem.
+dg-init
+if { [istarget rs6000-*-aix*]
+     || [istarget powerpc*-*-aix*]
+     || [istarget arm*-*-*]
+} {
+    set extra_flags ""
+} else {
+    set extra_flags "-fpic"
+}
+dg-runtest $srcdir/$subdir/981006-1.c "-Wuninitialized -O2 $extra_flags" ""
+dg-finish
+
 # 921210-1
 set lines [gcc_target_compile $srcdir/$subdir/921210-1.c "" preprocess ""]
 set lines [prune [split [prune_warnings [prune_gcc_output $lines]] "\n"] ""]