[flang-commits] [flang] [flang] Fix crash in name resolution (PR #85835)

[Peter Klausler via flang-commits]

https://github.com/klausler created https://github.com/llvm/llvm-project/pull/85835

ConvertToObjectEntity() returns true for use- and host-associated object symbols, too.  Ensure in this case that the symbol really is a non-associated object.

Fixes https://github.com/llvm/llvm-project/issues/85776.

>From fabb61942f31a7b3bdc8f361cef7d630aa3ee67c Mon Sep 17 00:00:00 2001
From: Peter Klausler <pklausler at nvidia.com>
Date: Tue, 19 Mar 2024 10:53:01 -0700
Subject: [PATCH] [flang] Fix crash in name resolution

ConvertToObjectEntity() returns true for use- and host-associated
object symbols, too.  Ensure in this case that the symbol
really is a non-associated object.

Fixes https://github.com/llvm/llvm-project/issues/85776.
---
 flang/lib/Semantics/resolve-names.cpp | 18 +++++++++---------
 flang/test/Semantics/resolve61.f90    |  9 +++++++++
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/flang/lib/Semantics/resolve-names.cpp b/flang/lib/Semantics/resolve-names.cpp
index b13674573fe07e..7ffc8eacaca6f4 100644
--- a/flang/lib/Semantics/resolve-names.cpp
+++ b/flang/lib/Semantics/resolve-names.cpp
@@ -4646,23 +4646,23 @@ bool DeclarationVisitor::Pre(const parser::OldParameterStmt &x) {
 bool DeclarationVisitor::Pre(const parser::NamedConstantDef &x) {
   auto &name{std::get<parser::NamedConstant>(x.t).v};
   auto &symbol{HandleAttributeStmt(Attr::PARAMETER, name)};
-  if (!ConvertToObjectEntity(symbol) ||
-      symbol.test(Symbol::Flag::CrayPointer) ||
+  ConvertToObjectEntity(symbol);
+  auto *details{symbol.detailsIf<ObjectEntityDetails>()};
+  if (!details || symbol.test(Symbol::Flag::CrayPointer) ||
       symbol.test(Symbol::Flag::CrayPointee)) {
     SayWithDecl(
         name, symbol, "PARAMETER attribute not allowed on '%s'"_err_en_US);
     return false;
   }
   const auto &expr{std::get<parser::ConstantExpr>(x.t)};
-  auto &details{symbol.get<ObjectEntityDetails>()};
-  if (details.init() || symbol.test(Symbol::Flag::InDataStmt)) {
+  if (details->init() || symbol.test(Symbol::Flag::InDataStmt)) {
     Say(name, "Named constant '%s' already has a value"_err_en_US);
   }
   if (inOldStyleParameterStmt_) {
     // non-standard extension PARAMETER statement (no parentheses)
     Walk(expr);
     auto folded{EvaluateExpr(expr)};
-    if (details.type()) {
+    if (details->type()) {
       SayWithDecl(name, symbol,
           "Alternative style PARAMETER '%s' must not already have an explicit type"_err_en_US);
     } else if (folded) {
@@ -4674,9 +4674,9 @@ bool DeclarationVisitor::Pre(const parser::NamedConstantDef &x) {
           } else if (auto shape{ToArraySpec(
                          GetFoldingContext(), evaluate::GetShape(*folded))}) {
             // The type of the named constant is assumed from the expression.
-            details.set_type(*type);
-            details.set_init(std::move(*folded));
-            details.set_shape(std::move(*shape));
+            details->set_type(*type);
+            details->set_init(std::move(*folded));
+            details->set_shape(std::move(*shape));
           } else {
             Say(at, "The expression must have constant shape"_err_en_US);
           }
@@ -4693,7 +4693,7 @@ bool DeclarationVisitor::Pre(const parser::NamedConstantDef &x) {
     Walk(expr);
     if (auto converted{EvaluateNonPointerInitializer(
             symbol, expr, expr.thing.value().source)}) {
-      details.set_init(std::move(*converted));
+      details->set_init(std::move(*converted));
     }
   }
   return false;
diff --git a/flang/test/Semantics/resolve61.f90 b/flang/test/Semantics/resolve61.f90
index 32bf9091a85651..2a1f584ffaf089 100644
--- a/flang/test/Semantics/resolve61.f90
+++ b/flang/test/Semantics/resolve61.f90
@@ -126,3 +126,12 @@ subroutine s
     pointer(ip, x) ! ok, local declaration
   end
 end
+
+subroutine p14
+  real :: r
+  block
+    asynchronous :: r
+    !ERROR: PARAMETER attribute not allowed on 'r'
+    parameter (r = 1.0)
+  end block
+end