[flang-commits] [flang] 0eb3299 - [flang] Fix crash from -DMACRO= with empty replacement

[peter klausler via flang-commits]

Author: peter klausler
Date: 2021-04-24T10:56:25-07:00
New Revision: 0eb3299d28e4a9e235dec28d70a0df9e74e74722

URL: https://github.com/llvm/llvm-project/commit/0eb3299d28e4a9e235dec28d70a0df9e74e74722
DIFF: https://github.com/llvm/llvm-project/commit/0eb3299d28e4a9e235dec28d70a0df9e74e74722.diff

LOG: [flang] Fix crash from -DMACRO= with empty replacement

Such macros were exposing some edge cases in the preprocessor
regarding empty tokens.

Differential Revision: https://reviews.llvm.org/D101207

Added: 
    

Modified: 
    flang/include/flang/Common/interval.h
    flang/lib/Parser/provenance.cpp

Removed: 
    


################################################################################
diff  --git a/flang/include/flang/Common/interval.h b/flang/include/flang/Common/interval.h
index c1ef8d72eb303..9d819f0364915 100644
--- a/flang/include/flang/Common/interval.h
+++ b/flang/include/flang/Common/interval.h
@@ -93,7 +93,7 @@ template <typename A> class Interval {
     return x - start_;
   }
   A OffsetMember(std::size_t n) const {
-    CHECK(n < size_);
+    CHECK(n <= size_);
     return start_ + n;
   }
 

diff  --git a/flang/lib/Parser/provenance.cpp b/flang/lib/Parser/provenance.cpp
index 2aa1a97ce5570..86de7657f9615 100644
--- a/flang/lib/Parser/provenance.cpp
+++ b/flang/lib/Parser/provenance.cpp
@@ -91,7 +91,10 @@ void OffsetToProvenanceMappings::Put(const OffsetToProvenanceMappings &that) {
 }
 
 ProvenanceRange OffsetToProvenanceMappings::Map(std::size_t at) const {
-  //  CHECK(!provenanceMap_.empty());
+  if (provenanceMap_.empty()) {
+    CHECK(at == 0);
+    return {};
+  }
   std::size_t low{0}, count{provenanceMap_.size()};
   while (count > 1) {
     std::size_t mid{low + (count >> 1)};