[clang][Interp] Fix casting function pointers to integers

2 files changed, 14 insertions, 0 deletions

diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index accaea0..3ceccfd 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -212,6 +212,13 @@ bool ByteCodeExprGen<Emitter>::VisitCastExpr(const CastExpr *CE) {
     if (!this->visit(SubExpr))
       return false;
 
+    // If SubExpr doesn't result in a pointer, make it one.
+    if (PrimType FromT = classifyPrim(SubExpr->getType()); FromT != PT_Ptr) {
+      assert(isPtrType(FromT));
+      if (!this->emitDecayPtr(FromT, PT_Ptr, CE))
+        return false;
+    }
+
     PrimType T = classifyPrim(CE->getType());
     if (T == PT_IntAP)
       return this->emitCastPointerIntegralAP(Ctx.getBitWidth(CE->getType()),
diff --git a/clang/test/AST/Interp/c.c b/clang/test/AST/Interp/c.c
index a595115..207da5f 100644
--- a/clang/test/AST/Interp/c.c
+++ b/clang/test/AST/Interp/c.c
@@ -263,3 +263,10 @@ const int *p = &b;
 const __int128 K = (__int128)(int*)0;
 const unsigned __int128 KU = (unsigned __int128)(int*)0;
 #endif
+
+
+int test3(void) {
+  int a[2];
+  a[0] = test3; // all-error {{incompatible pointer to integer conversion assigning to 'int' from 'int (void)'}}
+  return 0;
+}