Fix a loop overrun in ComputePreamble when the last remapped file was erased,

and reenable crash recovery test.
 - Reparsing is still very crashy / weird, so I had to sprinkle random code into
   the remapped input to get it to do what I want (i.e., crash!).

llvm-svn: 111550

3 files changed, 17 insertions, 9 deletions

diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index 523b8d0a6c2..4395246f493 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -850,6 +850,8 @@ ASTUnit::ComputePreamble(CompilerInvocation &Invocation,
           // Remove this remapping. We've captured the buffer already.
           M = PreprocessorOpts.eraseRemappedFile(M);
           E = PreprocessorOpts.remapped_file_end();
+          if (M == E)
+            break;
         }
       }
     }
@@ -875,6 +877,8 @@ ASTUnit::ComputePreamble(CompilerInvocation &Invocation,
           // Remove this remapping. We've captured the buffer already.
           M = PreprocessorOpts.eraseRemappedFile(M);
           E = PreprocessorOpts.remapped_file_buffer_end();
+          if (M == E)
+            break;
         }
       }
     }
diff --git a/clang/test/Index/Inputs/crash-recovery-reparse-remap.c b/clang/test/Index/Inputs/crash-recovery-reparse-remap.c
index 8a7707a5902..0357dbe748a 100644
--- a/clang/test/Index/Inputs/crash-recovery-reparse-remap.c
+++ b/clang/test/Index/Inputs/crash-recovery-reparse-remap.c
@@ -1,3 +1,11 @@
+
 #warning parsing remapped file
 
+
+
+int x;
+
 #pragma clang __debug crash
+
+int x;
+
diff --git a/clang/test/Index/crash-recovery-reparse.c b/clang/test/Index/crash-recovery-reparse.c
index 90ce25d1ad2..0697576880f 100644
--- a/clang/test/Index/crash-recovery-reparse.c
+++ b/clang/test/Index/crash-recovery-reparse.c
@@ -1,12 +1,8 @@
-// Disabled, pending investigation.
-// RUN: false
-// XFAIL: *
-//
-// RUNX: env CINDEXTEST_EDITING=1 \
-// RUNX:   not c-index-test -test-load-source-reparse 1 local \
-// RUNX:   -remap-file="%s;%S/Inputs/crash-recovery-reparse-remap.c" \
-// RUNX:   %s 2> %t.err
-// RUNX: FileCheck < %t.err -check-prefix=CHECK-REPARSE-SOURCE-CRASH %s
+// RUN: env CINDEXTEST_EDITING=1 \
+// RUN:   not c-index-test -test-load-source-reparse 1 local \
+// RUN:   -remap-file="%s;%S/Inputs/crash-recovery-reparse-remap.c" \
+// RUN:   %s 2> %t.err
+// RUN: FileCheck < %t.err -check-prefix=CHECK-REPARSE-SOURCE-CRASH %s
 // CHECK-REPARSE-SOURCE-CRASH: Unable to reparse translation unit
 //
 // XFAIL: win32