[clang] 771ad16 - [Clang] Fix a crash when recursively callig a default member initializer.

[Corentin Jabot via cfe-commits]

Author: Corentin Jabot
Date: 2023-05-01T23:21:14+02:00
New Revision: 771ad1691ac3057df2220dd327d7cdc73ef6c6f5

URL: https://github.com/llvm/llvm-project/commit/771ad1691ac3057df2220dd327d7cdc73ef6c6f5
DIFF: https://github.com/llvm/llvm-project/commit/771ad1691ac3057df2220dd327d7cdc73ef6c6f5.diff

LOG: [Clang] Fix a crash when recursively callig a default member initializer.

This fixes a regression introduced by ca61961380, that would lead
to a segfault due to stack exhaustion when recursively calling
a default member initializer.

Fixes #60082

I'm not able to  get clang to emit a stack exhaustion warning,
which it seems like it should be able to.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D142401

Added: 
    

Modified: 
    clang/docs/ReleaseNotes.rst
    clang/lib/Sema/SemaExpr.cpp

Removed: 
    


################################################################################
diff  --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index a3ee06ba1c22..34636faa36bf 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -313,8 +313,8 @@ Bug Fixes in This Version
   not a type concept.
 - Fix crash when a doc comment contains a line splicing.
   (`#62054 <https://github.com/llvm/llvm-project/issues/62054>`_)
-- Work around with a clang coverage crash which happens when visiting 
-  expressions/statements with invalid source locations in non-assert builds. 
+- Work around with a clang coverage crash which happens when visiting
+  expressions/statements with invalid source locations in non-assert builds.
   Assert builds may still see assertions triggered from this.
 - Fix a failed assertion due to an invalid source location when trying to form
   a coverage report for an unresolved constructor expression.
@@ -335,6 +335,8 @@ Bug Fixes in This Version
 - Fix crash when attempting to perform parenthesized initialization of an
   aggregate with a base class with only non-public constructors.
   (`#62296 <https://github.com/llvm/llvm-project/issues/62296>`_)
+- Fix a stack overflow issue when evaluating ``consteval`` default arguments.
+  (`#60082` <https://github.com/llvm/llvm-project/issues/60082>`_)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

diff  --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 5450b4748997..4edaf6970a2d 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -5926,7 +5926,9 @@ bool Sema::CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
       Param);
   ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer =
       SkipImmediateInvocations;
-  MarkDeclarationsReferencedInExpr(Init, /*SkipLocalVariables*/ true);
+  runWithSufficientStackSpace(CallLoc, [&] {
+    MarkDeclarationsReferencedInExpr(Init, /*SkipLocalVariables=*/true);
+  });
   return false;
 }
 
@@ -6036,8 +6038,11 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
       ExprEvalContexts.back().DelayedDefaultInitializationContext = {
           CallLoc, Param, CurContext};
       EnsureImmediateInvocationInDefaultArgs Immediate(*this);
-      ExprResult Res = Immediate.TransformInitializer(Param->getInit(),
-                                                      /*NotCopy=*/false);
+      ExprResult Res;
+      runWithSufficientStackSpace(CallLoc, [&] {
+        Res = Immediate.TransformInitializer(Param->getInit(),
+                                             /*NotCopy=*/false);
+      });
       if (Res.isInvalid())
         return ExprError();
       Res = ConvertParamDefaultArgument(Param, Res.get(),
@@ -6117,10 +6122,11 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
         NestedDefaultChecking;
 
     EnsureImmediateInvocationInDefaultArgs Immediate(*this);
-
-    ExprResult Res =
-        Immediate.TransformInitializer(Field->getInClassInitializer(),
-                                       /*CXXDirectInit=*/false);
+    ExprResult Res;
+    runWithSufficientStackSpace(Loc, [&] {
+      Res = Immediate.TransformInitializer(Field->getInClassInitializer(),
+                                           /*CXXDirectInit=*/false);
+    });
     if (!Res.isInvalid())
       Res = ConvertMemberDefaultInitExpression(Field, Res.get(), Loc);
     if (Res.isInvalid()) {
@@ -6133,7 +6139,9 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
   if (Field->getInClassInitializer()) {
     Expr *E = Init ? Init : Field->getInClassInitializer();
     if (!NestedDefaultChecking)
-      MarkDeclarationsReferencedInExpr(E, /*SkipLocalVariables=*/false);
+      runWithSufficientStackSpace(Loc, [&] {
+        MarkDeclarationsReferencedInExpr(E, /*SkipLocalVariables=*/false);
+      });
     // C++11 [class.base.init]p7:
     //   The initialization of each base and member constitutes a
     //   full-expression.
@@ -18545,7 +18553,9 @@ void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
   if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) {
     for (CXXCtorInitializer *Init : Constructor->inits()) {
       if (Init->isInClassMemberInitializer())
-        MarkDeclarationsReferencedInExpr(Init->getInit());
+        runWithSufficientStackSpace(Init->getSourceLocation(), [&]() {
+          MarkDeclarationsReferencedInExpr(Init->getInit());
+        });
     }
   }