[PATCH] D64409: [libclang] Fix hang in release / assertion in debug when evaluating value-dependent types.

[Emilio Cobos Álvarez via Phabricator via cfe-commits]

emilio created this revision.
emilio added reviewers: Anastasia, arphaman.
Herald added subscribers: cfe-commits, dexonsmith.
Herald added a project: clang.
emilio edited the summary of this revision.

Expression evaluator doesn't work in value-dependent types, so ensure that the
precondition it asserts holds.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42532.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D64409

Files:
  clang/test/Index/evaluate-cursor.cpp
  clang/tools/libclang/CIndex.cpp


Index: clang/tools/libclang/CIndex.cpp
===================================================================
--- clang/tools/libclang/CIndex.cpp
+++ clang/tools/libclang/CIndex.cpp
@@ -3782,6 +3782,8 @@
     return nullptr;
 
   expr = expr->IgnoreParens();
+  if (expr->isValueDependent())
+    return nullptr;
   if (!expr->EvaluateAsRValue(ER, ctx))
     return nullptr;
 
Index: clang/test/Index/evaluate-cursor.cpp
===================================================================
--- clang/test/Index/evaluate-cursor.cpp
+++ clang/test/Index/evaluate-cursor.cpp
@@ -21,6 +21,11 @@
 
 long long HUGE_NEG = -(1ll << 35);
 
+template <typename d> class e {
+  using f = d;
+  static const auto g = alignof(f);
+};
+
 // RUN: c-index-test -evaluate-cursor-at=%s:4:7 \
 // RUN:    -evaluate-cursor-at=%s:8:7 \
 // RUN:    -evaluate-cursor-at=%s:8:11 -std=c++11 %s | FileCheck %s
@@ -42,3 +47,9 @@
 // CHECK-LONG: unsigned, Value: 1152921504606846976
 // CHECK-LONG: unsigned, Value: 9223372036854775808
 // CHECK-LONG: Value: -34359738368
+
+// RUN: c-index-test -evaluate-cursor-at=%s:18:20 \
+// RUN:    -evaluate-cursor-at=%s:20:20 \
+// RUN:    -evaluate-cursor-at=%s:26:21 \
+// RUN:    -std=c++11 %s | FileCheck -check-prefix=CHECK-DOES-NOT-CRASH %s
+// CHECK-DOES-NOT-CRASH: Not Evaluatable


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