Adding a test for PR25717.

The test tries to produce a large preprocessed output to the console, and checks
that we do not see any unexpected fatal errors.

The test is not enabled unless a lit parameter "--param enable_console=1" is
passed on the command line to lit.py.

llvm-svn: 258902

clang/test/Preprocessor/bigoutput.c

@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -E -x c %s > /dev/tty
+// The original bug requires UNIX line endings to trigger.
+// The original bug triggers only when outputting directly to console.
+// REQUIRES: console
+
+// Make sure clang does not crash during preprocessing
+
+#define M0 extern int x;
+#define M2  M0  M0  M0  M0
+#define M4  M2  M2  M2  M2
+#define M6  M4  M4  M4  M4
+#define M8  M6  M6  M6  M6
+#define M10 M8  M8  M8  M8
+#define M12 M10 M10 M10 M10
+#define M14 M12 M12 M12 M12
+
+M14

clang/test/lit.cfg

@@ -491,4 +491,9 @@ gmalloc_path_str = lit_config.params.get('gmalloc_path',
 if use_gmalloc:
      config.environment.update({'DYLD_INSERT_LIBRARIES' : gmalloc_path_str})
 
+# Check if we should allow outputs to console.
+run_console_tests = int(lit_config.params.get('enable_console', '0'))
+if run_console_tests != 0:
+  config.available_features.add('console')
+
 lit.util.usePlatformSdkOnDarwin(config, lit_config)