diff --git a/clang/test/3C/allarrays.c b/clang/test/3C/allarrays.c
index 29c9e7a24846..ec55cce7577e 100644
--- a/clang/test/3C/allarrays.c
+++ b/clang/test/3C/allarrays.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
 
 int* foo();
 //CHECK: _Array_ptr<int> foo(_Array_ptr<int> r);
diff --git a/clang/test/3C/arrboundsadvanced.c b/clang/test/3C/arrboundsadvanced.c
index df629c951327..e273b90d2add 100644
--- a/clang/test/3C/arrboundsadvanced.c
+++ b/clang/test/3C/arrboundsadvanced.c
@@ -1,5 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
-
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
 
 /*
 Advanced array-bounds inference (based on control-dependencies).
@@ -17,12 +17,12 @@ struct foo1 {
     unsigned ml;    
 };
 //CHECK:     _Array_ptr<int> x : count(ml);
+unsigned FooLenD;
+unsigned FooLen;
 struct foo **FL;
 int *intarr;
 //CHECK: _Array_ptr<_Ptr<struct foo>> FL : count(FooLen) = ((void *)0);
 //CHECK: _Array_ptr<int> intarr = ((void *)0);
-unsigned FooLenD;
-unsigned FooLen;
 void intcopy(int *arr, int *ptr, int len) {
     int i;
     for (i=0; i<len; i++) {
diff --git a/clang/test/3C/arrboundsbasic.c b/clang/test/3C/arrboundsbasic.c
index 3ae33d7b4cc4..c89b277b0676 100644
--- a/clang/test/3C/arrboundsbasic.c
+++ b/clang/test/3C/arrboundsbasic.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
 
 /*
diff --git a/clang/test/3C/arrboundsbasicinfer.c b/clang/test/3C/arrboundsbasicinfer.c
index e31cba2b49b3..db7f057c5ac6 100644
--- a/clang/test/3C/arrboundsbasicinfer.c
+++ b/clang/test/3C/arrboundsbasicinfer.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
 
 /*
diff --git a/clang/test/3C/arrboundsbyte.c b/clang/test/3C/arrboundsbyte.c
index 94032f7a4a38..7aa39c3b6c20 100644
--- a/clang/test/3C/arrboundsbyte.c
+++ b/clang/test/3C/arrboundsbyte.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
 
 /*
diff --git a/clang/test/3C/arrboundsheuristics.c b/clang/test/3C/arrboundsheuristics.c
index fbb1506d8707..7004676c222f 100644
--- a/clang/test/3C/arrboundsheuristics.c
+++ b/clang/test/3C/arrboundsheuristics.c
@@ -2,8 +2,10 @@
 //
 // Checks wrong array heuristics.
 //
-//RUN: 3c -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
-//RUN: 3c %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
+// RUN: 3c %s | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t2.unused -
 
 int *glob;
 int lenplusone;
diff --git a/clang/test/3C/arrboundsinfer2.c b/clang/test/3C/arrboundsinfer2.c
index b683fc90d9dc..fa624463afa7 100644
--- a/clang/test/3C/arrboundsinfer2.c
+++ b/clang/test/3C/arrboundsinfer2.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
 
 /*
diff --git a/clang/test/3C/arrtestsBUG.c b/clang/test/3C/arrtests_xfail.c
similarity index 96%
rename from clang/test/3C/arrtestsBUG.c
rename to clang/test/3C/arrtests_xfail.c
index 04d8cd2d0382..24a0a03e14f0 100644
--- a/clang/test/3C/arrtestsBUG.c
+++ b/clang/test/3C/arrtests_xfail.c
@@ -1,5 +1,6 @@
-// XFAIL: *
 // RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
+
 // XFAIL: *
 
 /*
diff --git a/clang/test/3C/basic_inter.c b/clang/test/3C/basic_inter.c
index 09610849cfbc..36177ec00553 100644
--- a/clang/test/3C/basic_inter.c
+++ b/clang/test/3C/basic_inter.c
@@ -2,7 +2,8 @@
 //
 // Tests properties about constraint propagation between functions.
 //
-// RUN: 3c %s -- | FileCheck -match-full-lines %s
+// RUN: 3c %s | FileCheck -match-full-lines %s
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 //
 
 int funcdecl(int *ptr, int *iptr, int *wild);
diff --git a/clang/test/3C/basic_inter_field_ntarr.c b/clang/test/3C/basic_inter_field_ntarr.c
index ec5178a03560..07869b3e11f1 100644
--- a/clang/test/3C/basic_inter_field_ntarr.c
+++ b/clang/test/3C/basic_inter_field_ntarr.c
@@ -2,7 +2,8 @@
 //
 // Tests rewriting of Nt_array_ptrs within structure fields
 
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
 //
 
 unsigned long strlen(const char *s : itype(_Nt_array_ptr<const char>)) ;
diff --git a/clang/test/3C/basic_inter_ntarr.c b/clang/test/3C/basic_inter_ntarr.c
index 9613f244ab4c..8f3634ffbd24 100644
--- a/clang/test/3C/basic_inter_ntarr.c
+++ b/clang/test/3C/basic_inter_ntarr.c
@@ -2,7 +2,8 @@
 //
 // Tests rewriting and propagation of Nt_array_ptr constraints across functions.
 //
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 //
 char *strstr(const char *s1 : itype(_Nt_array_ptr<const char>),
              const char *s2 : itype(_Nt_array_ptr<const char>)) : itype(_Nt_array_ptr<char>);
diff --git a/clang/test/3C/basic_local_ntarr.c b/clang/test/3C/basic_local_ntarr.c
index f03d89e588d4..cae3598b9136 100644
--- a/clang/test/3C/basic_local_ntarr.c
+++ b/clang/test/3C/basic_local_ntarr.c
@@ -2,7 +2,8 @@
 //
 // Tests basic rewriting of Nt_array_ptrs
 
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
 //
 
 unsigned long strlen(const char *s : itype(_Nt_array_ptr<const char>));
@@ -18,7 +19,7 @@ int main() {
   int b;
   // this will make a as NTARR
   b = strlen(a);
-  // this will make C as NTArr
+  // this will make C as PTR
   c = strstr("Hello", "World");
   // this should mark d as WILD.
   d = (int*)0xdeadbeef;
diff --git a/clang/test/3C/basic_return_itype.c b/clang/test/3C/basic_return_itype.c
index 6616d371ac1b..84dab39e870a 100644
--- a/clang/test/3C/basic_return_itype.c
+++ b/clang/test/3C/basic_return_itype.c
@@ -2,7 +2,8 @@
 //
 // Tests properties about rewriter for return type when it is an itype
 //
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 //
 
 static int funcvar;
diff --git a/clang/test/3C/checkedregionvoid.c b/clang/test/3C/checkedregionvoid.c
index 0dc9c3fead55..629c0568eb65 100644
--- a/clang/test/3C/checkedregionvoid.c
+++ b/clang/test/3C/checkedregionvoid.c
@@ -1,7 +1,7 @@
-// RUN: 3c -addcr  %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
-#include "dummy.h"
-// Dummy to cause output
+void unsafe(void *);// Dummy to cause output
 void f(int *x) {}
 //CHECK: void f(_Ptr<int> x) _Checked {}
 
diff --git a/clang/test/3C/contextsensitivebounds.c b/clang/test/3C/contextsensitivebounds.c
index 226de455523d..5988bdc51031 100644
--- a/clang/test/3C/contextsensitivebounds.c
+++ b/clang/test/3C/contextsensitivebounds.c
@@ -2,8 +2,11 @@
 Test for context sensitive bounds.
 **/
 
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
-// RUN: 3c %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unusedl -
+// RUN: 3c %s | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t2.unused -
+
 _Itype_for_any(T) void *somefunc(unsigned long size) : itype(_Array_ptr<T>) byte_count(size);
 struct hash_node
 {
diff --git a/clang/test/3C/contextsensitivebounds1.c b/clang/test/3C/contextsensitivebounds1.c
index 115a70bd414f..71d0cd1a13ff 100644
--- a/clang/test/3C/contextsensitivebounds1.c
+++ b/clang/test/3C/contextsensitivebounds1.c
@@ -2,8 +2,11 @@
 Test for context sensitive bounds for internal functions.
 **/
 
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
-// RUN: 3c %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
+// RUN: 3c %s | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t2.unused -
+
 _Itype_for_any(T) void *somefunc(unsigned long size) : itype(_Array_ptr<T>) byte_count(size);
 struct hash_node
 {
diff --git a/clang/test/3C/difftypes_xfail1.c b/clang/test/3C/difftypes_xfail1.c
index 2e5adef83f15..b44fe2230815 100644
--- a/clang/test/3C/difftypes_xfail1.c
+++ b/clang/test/3C/difftypes_xfail1.c
@@ -1,4 +1,7 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked %s %S/difftypes_xfail2.c
-// XFAIL: * 
+
+// XFAIL: *
+
+// The desired behavior in this case is to fail, so other checks are omitted
 
 _Ptr<int> foo(int, char);
diff --git a/clang/test/3C/difftypes_xfail2.c b/clang/test/3C/difftypes_xfail2.c
index 9b1b1a09113c..d85951033c95 100644
--- a/clang/test/3C/difftypes_xfail2.c
+++ b/clang/test/3C/difftypes_xfail2.c
@@ -1,4 +1,7 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked %s %S/difftypes_xfail1.c
+
 // XFAIL: *
 
+// The desired behavior in this case is to fail, so other checks are omitted
+
 int * foo(int, char *);
diff --git a/clang/test/3C/dummy.h b/clang/test/3C/dummy.h
deleted file mode 100644
index 6dc452825056..000000000000
--- a/clang/test/3C/dummy.h
+++ /dev/null
@@ -1,2 +0,0 @@
-
-void unsafe(void *);
diff --git a/clang/test/3C/extGVarbar1.c b/clang/test/3C/extGVarbar1.c
index 06b9b6fad05b..4247c3e9c79a 100644
--- a/clang/test/3C/extGVarbar1.c
+++ b/clang/test/3C/extGVarbar1.c
@@ -3,7 +3,7 @@
 //RUN: %clang -c %S/extGVarbar1.checked.c %S/extGVarbar2.checked.c
 //RUN: rm %S/extGVarbar1.checked.c %S/extGVarbar2.checked.c
 
-/*first of the bar files*/ 
+// This test cannot use pipes because it requires multiple output files
 
 extern int *x; 
 /*y will be defined in bar2.c*/
diff --git a/clang/test/3C/extGVarbar2.c b/clang/test/3C/extGVarbar2.c
index af1f14e1bb44..6183f2599da2 100644
--- a/clang/test/3C/extGVarbar2.c
+++ b/clang/test/3C/extGVarbar2.c
@@ -1,8 +1,9 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked2 %s %S/extGVarbar1.c
 //RUN: FileCheck -match-full-lines --input-file %S/extGVarbar2.checked2.c %s
+//RUN: %clang -c %S/extGVarbar2.checked2.c %S/extGVarbar1.checked2.c
 //RUN: rm %S/extGVarbar1.checked2.c %S/extGVarbar2.checked2.c
 
-/*second of the bar files*/ 
+// This test cannot use pipes because it requires multiple output files
 
 int w = 2;
 int *y = &w; 
diff --git a/clang/test/3C/extGVarm1.c b/clang/test/3C/extGVarm1.c
index 90007b5d5cb0..0ce4cc8f6950 100644
--- a/clang/test/3C/extGVarm1.c
+++ b/clang/test/3C/extGVarm1.c
@@ -3,6 +3,8 @@
 //RUN: %clang -c %S/extGVarm1.checked.c %S/extGVarm2.checked.c %S/extGVarm3.checked.c
 //RUN: rm %S/extGVarm1.checked.c %S/extGVarm2.checked.c %S/extGVarm3.checked.c
 
+// This test cannot use pipes because it requires multiple output files
+
 extern int *y; 
 //CHECK: extern _Ptr<int> y; 
 
diff --git a/clang/test/3C/extGVarm2.c b/clang/test/3C/extGVarm2.c
index c9739aa5394e..2eb0404ad30a 100644
--- a/clang/test/3C/extGVarm2.c
+++ b/clang/test/3C/extGVarm2.c
@@ -1,7 +1,10 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked2 %s %S/extGVarm1.c %S/extGVarm3.c
 //RUN: FileCheck -match-full-lines --input-file %S/extGVarm2.checked2.c %s
+//RUN: %clang -c %S/extGVarm2.checked2.c %S/extGVarm3.checked2.c %S/extGVarm1.checked2.c
 //RUN: rm %S/extGVarm1.checked2.c %S/extGVarm2.checked2.c %S/extGVarm3.checked2.c
 
+// This test cannot use pipes because it requires multiple output files
+
 extern int *x;
 //CHECK: extern int *x; 
 
diff --git a/clang/test/3C/extGVarm3.c b/clang/test/3C/extGVarm3.c
index a38b550b9dde..162406a31235 100644
--- a/clang/test/3C/extGVarm3.c
+++ b/clang/test/3C/extGVarm3.c
@@ -1,7 +1,10 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked3 %s %S/extGVarm1.c %S/extGVarm2.c
 //RUN: FileCheck -match-full-lines --input-file %S/extGVarm3.checked3.c %s
+//RUN: %clang -c %S/extGVarm3.checked3.c %S/extGVarm2.checked3.c %S/extGVarm1.checked3.c
 //RUN: rm %S/extGVarm1.checked3.c %S/extGVarm2.checked3.c %S/extGVarm3.checked3.c 
 
+// This test cannot use pipes because it requires multiple output files
+
 extern int *x; 
 //CHECK: extern int *x;
 
diff --git a/clang/test/3C/hash.c b/clang/test/3C/hash.c
index 00a04362d899..401568bd5f30 100644
--- a/clang/test/3C/hash.c
+++ b/clang/test/3C/hash.c
@@ -1,4 +1,8 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+
+// Currently not possible to run clang on the output,
+// there is an error reported at https://github.com/correctcomputation/checkedc-clang/issues/349
+
 /*
  * Based on hash.c in Very Secure FTPd
  */
diff --git a/clang/test/3C/lit.local.cfg b/clang/test/3C/lit.local.cfg
index 5ab27370c9bf..856a54932f0b 100644
--- a/clang/test/3C/lit.local.cfg
+++ b/clang/test/3C/lit.local.cfg
@@ -1,6 +1 @@
-# import os
 config.suffixes = ['.c']
-# config.environment = {
-# 'CHECKED_CPATH':'/Users/mwh/checkedc/checkedc/include/:',
-# 'PATH':'/Users/mwh/checkedc/checkedc-clang/llvm/cmake-debug-build/bin:'+os.getenv('PATH')
-# }
diff --git a/clang/test/3C/lowerbound.c b/clang/test/3C/lowerbound.c
index 85d36226916e..da6d774b0950 100644
--- a/clang/test/3C/lowerbound.c
+++ b/clang/test/3C/lowerbound.c
@@ -1,7 +1,8 @@
 // Generates graph q0 --> ARR --> q1, to confirm that bound bound
 //   constraints are properly solved
 // The following test is supposed to fail with the current tool.
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t.unused -
 //
 
 _Array_ptr<int> foo(_Array_ptr<int> x);
diff --git a/clang/test/3C/lowerboundBUG.c b/clang/test/3C/lowerboundBUG.c
deleted file mode 100644
index 85d36226916e..000000000000
--- a/clang/test/3C/lowerboundBUG.c
+++ /dev/null
@@ -1,15 +0,0 @@
-// Generates graph q0 --> ARR --> q1, to confirm that bound bound
-//   constraints are properly solved
-// The following test is supposed to fail with the current tool.
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
-//
-
-_Array_ptr<int> foo(_Array_ptr<int> x);
-void bar() {
-  int *y = 0;
-  int *z = 0;
-  y = foo(z);
-  y[2] = 1;
-}
-//CHECK: _Array_ptr<int> y =  0;
-//CHECK-NEXT: _Array_ptr<int> z =  0;
diff --git a/clang/test/3C/manyprotos.c b/clang/test/3C/manyprotos.c
index 593b1472a417..d3d402128fae 100644
--- a/clang/test/3C/manyprotos.c
+++ b/clang/test/3C/manyprotos.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t1.unused -
 
 int foo();
 //CHECK: int foo(_Array_ptr<int> x : count(y), int y);
diff --git a/clang/test/3C/multidef_xfail1.c b/clang/test/3C/multidef_xfail1.c
index 551a223ae7a9..b556b7c03d52 100644
--- a/clang/test/3C/multidef_xfail1.c
+++ b/clang/test/3C/multidef_xfail1.c
@@ -1,6 +1,9 @@
-//RUN: 3c -base-dir=%S -output-postfix=checked %s %S/multidef_xfail2.c
+// RUN: 3c -base-dir=%S -output-postfix=checked %s %S/multidef_xfail2.c
+
 // XFAIL: *
 
+// The desired behavior in this case is to fail, so other checks are omitted
+
 _Ptr<int> foo(int x, char * y) { 
     x = x + 4; 
     int *z = &x; 
diff --git a/clang/test/3C/multidef_xfail2.c b/clang/test/3C/multidef_xfail2.c
index 0f13b3f006ae..e2a8ce5022c7 100644
--- a/clang/test/3C/multidef_xfail2.c
+++ b/clang/test/3C/multidef_xfail2.c
@@ -1,5 +1,8 @@
-//RUN: 3c -base-dir=%S -output-postfix=checked %s %S/multidef_xfail1.c
-// XFAIL: * 
+// RUN: 3c -base-dir=%S -output-postfix=checked %s %S/multidef_xfail1.c
+
+// XFAIL: *
+
+// The desired behavior in this case is to fail, so other checks are omitted
 
 int * foo(int x, _Ptr<char> y) { 
     x = x + 4; 
diff --git a/clang/test/3C/no_casts.c b/clang/test/3C/no_casts.c
index 366f9bb5fae4..a858d451fcd8 100644
--- a/clang/test/3C/no_casts.c
+++ b/clang/test/3C/no_casts.c
@@ -1,4 +1,5 @@
 // RUN: 3c %s | count 0
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 
 void foo(char *a);
 void bar(int *a);
diff --git a/clang/test/3C/noproto.c b/clang/test/3C/noproto.c
index 1e2bd05937cf..cece19c80b60 100644
--- a/clang/test/3C/noproto.c
+++ b/clang/test/3C/noproto.c
@@ -1,4 +1,5 @@
-// RUN: 3c -addcr  %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 
 int foo(int x) { 
   //CHECK: int foo(int x) {
diff --git a/clang/test/3C/order.c b/clang/test/3C/order.c
index 6a7c9e33aeed..b5e12893eddd 100644
--- a/clang/test/3C/order.c
+++ b/clang/test/3C/order.c
@@ -1,4 +1,5 @@
-// RUN: 3c %s -- | FileCheck -match-full-lines %s
+// RUN: 3c %s | FileCheck -match-full-lines %s
+// RUN: 3c %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 
 int foo1(int x, int *y);
 //CHECK: int foo1(int x, int *y : itype(_Ptr<int>));
diff --git a/clang/test/3C/partial_checked_arr.c b/clang/test/3C/partial_checked_arr.c
index f664f2115377..c1c6c54ca73c 100644
--- a/clang/test/3C/partial_checked_arr.c
+++ b/clang/test/3C/partial_checked_arr.c
@@ -1,8 +1,9 @@
-// RUN: 3c -addcr -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
-// RUN: 3c -addcr %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
-// RUN: 3c -alltypes -output-postfix=checked %s
-// RUN: 3c -alltypes %S/partial_checked_arr.checked.c -- | count 0
-// RUN: rm %S/partial_checked_arr.checked.c
+// RUN: 3c -addcr -alltypes %s | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
+// RUN: 3c -addcr -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t1.unused -
+// RUN: 3c -addcr %s | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
+// RUN: 3c -addcr %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t2.unused -
+// RUN: 3c -alltypes %s > %t
+// RUN: 3c -alltypes %t | count 0
 
 int strcmp(const char *src1 : itype(_Nt_array_ptr<const char>),
            const char *src2 : itype(_Nt_array_ptr<const char>));
diff --git a/clang/test/3C/patch_issue_272.c b/clang/test/3C/patch_issue_272.c
index d4650a89c07a..a96ad33e2a7a 100644
--- a/clang/test/3C/patch_issue_272.c
+++ b/clang/test/3C/patch_issue_272.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t.unused -
 
 /********************************************************************/
 /* Tests to keep pointer level from                                 */
diff --git a/clang/test/3C/pointerarithm.c b/clang/test/3C/pointerarithm.c
index 42312aefcd1d..3132a79efb4b 100644
--- a/clang/test/3C/pointerarithm.c
+++ b/clang/test/3C/pointerarithm.c
@@ -1,6 +1,7 @@
-// RUN: 3c -alltypes -addcr %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes -addcr %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes -addcr %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 // RUN: 3c -addcr -alltypes -output-postfix=checked %s 
-// RUN: 3c -addcr -alltypes %S/pointerarithm.checked.c -- | count 0
+// RUN: 3c -addcr -alltypes %S/pointerarithm.checked.c | count 0
 // RUN: rm %S/pointerarithm.checked.c
 
 #include <stddef.h>
diff --git a/clang/test/3C/prototype_success2.c b/clang/test/3C/prototype_success2.c
index 077184aee051..95ea4cc83598 100644
--- a/clang/test/3C/prototype_success2.c
+++ b/clang/test/3C/prototype_success2.c
@@ -1,5 +1,6 @@
 //RUN: 3c -base-dir=%S -output-postfix=checked2 %s %S/prototype_success1.c
 //RUN: FileCheck -match-full-lines --input-file %S/prototype_success2.checked2.c %s
+//RUN: %clang -c %S/prototype_success1.checked2.c %S/prototype_success2.checked2.c
 //RUN: rm %S/prototype_success1.checked2.c %S/prototype_success2.checked2.c 
 
 /*Note: this file is part of a multi-file regression test in tandem with prototype_success1.c 
diff --git a/clang/test/3C/regression_testsBUG.c b/clang/test/3C/regression_tests_xfail.c
similarity index 81%
rename from clang/test/3C/regression_testsBUG.c
rename to clang/test/3C/regression_tests_xfail.c
index 7f43821ac6ed..db0ad5149b26 100644
--- a/clang/test/3C/regression_testsBUG.c
+++ b/clang/test/3C/regression_tests_xfail.c
@@ -2,9 +2,8 @@
 //
 // Tests 3c tool for any regressions.
 //
-// The following test is supposed to fail with the current tool.
-// XFAIL: *
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines %s
+// RUN: 3c -alltypes %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 // 
 // XFAIL: *
 
diff --git a/clang/test/3C/root_cause.c b/clang/test/3C/root_cause.c
index a00450f3c5d8..cb625f09eb04 100644
--- a/clang/test/3C/root_cause.c
+++ b/clang/test/3C/root_cause.c
@@ -1,4 +1,6 @@
-// RUN: 3c -extra-arg="-Wno-everything" -alltypes -warn-root-cause %s 2>&1 1>/dev/null | FileCheck %s
+// RUN: 3c -extra-arg="-Wno-everything" -alltypes -warn-root-cause %s 2>&1 1>%t.unused | FileCheck %s
+
+// This test is unusual in that it checks for the errors in the code
 
 #include <stddef.h>
 extern _Itype_for_any(T) void *malloc(size_t size) : itype(_Array_ptr<T>) byte_count(size);
diff --git a/clang/test/3C/stmtexpr.c b/clang/test/3C/stmtexpr.c
index bb71ac57c565..5e4f4653fd9a 100644
--- a/clang/test/3C/stmtexpr.c
+++ b/clang/test/3C/stmtexpr.c
@@ -1,4 +1,5 @@
-// RUN: 3c -addcr  %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -addcr %s | %clang -c -fcheckedc-extension -x c -o %t.unused -
 
 int foo(void) { 
 //CHECK: int foo(void) {
@@ -8,5 +9,5 @@ int foo(void) {
 // Dummy function to ensure output
 int dummy(int *x) { 
 //CHECK: int dummy(_Ptr<int> x) _Checked {
-  return x;
+  return *x;
 }
diff --git a/clang/test/3C/untypedprototypes.c b/clang/test/3C/untypedprototypes.c
index b0eda72c721f..7fe7fb54774d 100644
--- a/clang/test/3C/untypedprototypes.c
+++ b/clang/test/3C/untypedprototypes.c
@@ -1,4 +1,5 @@
-// RUN: 3c -alltypes %s -- | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | FileCheck -match-full-lines --check-prefixes="CHECK" %s
+// RUN: 3c -alltypes %s | %clang -c -f3c-tool -fcheckedc-extension -x c -o %t.unused -
 
 int *foo();
 //CHECK: _Array_ptr<int> foo(_Array_ptr<int> q);