[Clang] Fix looking for immediate calls in default arguments.

[cor3ntin]

Due to improper use of RecursiveASTVisitor.

Fixes #80630

[llvmbot]

@llvm/pr-subscribers-clang

Author: cor3ntin (cor3ntin)

Changes

Due to improper use of RecursiveASTVisitor.

Fixes #80630

---

Full diff: https://github.com/llvm/llvm-project/pull/80690.diff

4 Files Affected:

• (modified) clang/docs/ReleaseNotes.rst (+2)
• (modified) clang/lib/Sema/SemaExpr.cpp (+3-3)
• (modified) clang/test/SemaCXX/cxx2a-consteval-default-params.cpp (+15)
• (modified) clang/test/SemaCXX/source_location.cpp (+18)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 3596109bf044f..fc9acd3f20792 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -201,6 +201,8 @@ Bug Fixes to C++ Support
   parameter where we did an incorrect specialization of the initialization of
   the default parameter.
   Fixes (`#68490 <https://github.com/llvm/llvm-project/issues/68490>`_)
+- Fix evaluation of some immediate calls in default arguments.
+  Fixes (`#80630 <https://github.com/llvm/llvm-project/issues/80630>`_)
 
 Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index d15278bce5a6b..ab212447f7368 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -6198,7 +6198,7 @@ struct ImmediateCallVisitor : public RecursiveASTVisitor<ImmediateCallVisitor> {
   bool VisitCallExpr(CallExpr *E) {
     if (const FunctionDecl *FD = E->getDirectCallee())
       HasImmediateCalls |= FD->isImmediateFunction();
-    return RecursiveASTVisitor<ImmediateCallVisitor>::VisitStmt(E);
+    return RecursiveASTVisitor<ImmediateCallVisitor>::VisitCallExpr(E);
   }
 
   // SourceLocExpr are not immediate invocations
@@ -6222,9 +6222,9 @@ struct ImmediateCallVisitor : public RecursiveASTVisitor<ImmediateCallVisitor> {
 
   // Blocks don't support default parameters, and, as for lambdas,
   // we don't consider their body a subexpression.
-  bool VisitBlockDecl(BlockDecl *B) { return false; }
+  bool VisitBlockDecl(BlockDecl *B) { return true; }
 
-  bool VisitCompoundStmt(CompoundStmt *B) { return false; }
+  bool VisitCompoundStmt(CompoundStmt *B) { return true; }
 
   bool VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
     return TraverseStmt(E->getExpr());
diff --git a/clang/test/SemaCXX/cxx2a-consteval-default-params.cpp b/clang/test/SemaCXX/cxx2a-consteval-default-params.cpp
index be8f7cc788589..e4b13725b2dac 100644
--- a/clang/test/SemaCXX/cxx2a-consteval-default-params.cpp
+++ b/clang/test/SemaCXX/cxx2a-consteval-default-params.cpp
@@ -82,3 +82,18 @@ namespace GH62224 {
   C<> Val; // No error since fwd is defined already.
   static_assert(Val.get() == 42);
 }
+
+namespace GH80630 {
+
+consteval const char* ce() { return "Hello"; }
+
+auto f2(const char* loc = []( char const* fn )
+    { return fn; }  ( ce() ) ) {
+    return loc;
+}
+
+auto g() {
+    return f2();
+}
+
+}
diff --git a/clang/test/SemaCXX/source_location.cpp b/clang/test/SemaCXX/source_location.cpp
index 7414fbce7828d..b151fc45fdad6 100644
--- a/clang/test/SemaCXX/source_location.cpp
+++ b/clang/test/SemaCXX/source_location.cpp
@@ -832,3 +832,21 @@ void test() {
 }
 
 }
+
+namespace GH80630 {
+
+#define GH80630_LAMBDA \
+    []( char const* fn ) { \
+        static constexpr std::source_location loc = std::source_location::current(); \
+        return &loc; \
+    }( std::source_location::current().function() )
+
+auto f( std::source_location const* loc = GH80630_LAMBDA ) {
+    return loc;
+}
+
+auto g() {
+    return f();
+}
+
+}

[AaronBallman]

I think we can just remove these entirely; the default implementation already returns true.

[AaronBallman]

This is a noop, right? If so, I'd drop the changes here but make an NFC change for this and the one in VisitSourceLocExpr() at the same time.

[AaronBallman]

LGTM!

[zyn0217]

Does this fix #67134 as well?

[cor3ntin]

Does this fix #67134 as well?

I don't think so, no