Make sure we add parent decls until the TranslationUnit

Due to the recursive nature of C++, we must make sure we added all Decls up to the root (TranslationUnitDecl) of the AST to the output, else we might miss important decls. Signed-off-by: Giuliano Belinassi <[email protected]>
SUSE · Sep 26, 2024 · 19a5ea3 · 19a5ea3
1 parent 9c0254f
commit 19a5ea3
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Showing 4 changed files with 36,303 additions and 7 deletions.
diff --git a/libcextract/Closure.cpp b/libcextract/Closure.cpp
@@ -212,13 +212,6 @@ bool DeclClosureVisitor::VisitDeclaratorDecl(DeclaratorDecl *decl)
      comming from comma-separated.  */
   TRY_TO(AnalyzeDeclsWithSameBeginlocHelper(decl));
 
-  /* Look for the LinkageSpecDecl in order to catch constructions such as:
-   *  extern "C" memcpy(void *, void *, unsigned long n);
-   */
-  if (LinkageSpecDecl *link = dyn_cast<LinkageSpecDecl>(decl->getLexicalDeclContext())) {
-    Closure.Add_Single_Decl(link);
-  }
-
   return VISITOR_CONTINUE;
 }
 
@@ -338,6 +331,22 @@ bool DeclClosureVisitor::VisitVarDecl(VarDecl *decl)
   return VISITOR_CONTINUE;
 }
 
+bool DeclClosureVisitor::VisitNamedDecl(NamedDecl *decl)
+{
+  /* Make sure we recusively add the parent decls in order to output this
+     decl we marked as visited.  For example where we need this see
+     c++-linkage-4.cpp, where the definition of align_val_t is inside a
+     LinkageDecl inside a NamespaceDecl.  */
+  DeclContext *ctx = decl->getLexicalDeclContext();
+  while (ctx) {
+    Decl *d = cast<Decl>(ctx);
+    Closure.Add_Single_Decl(d);
+    ctx = ctx->getParent();
+  }
+
+  return VISITOR_CONTINUE;
+}
+
 bool DeclClosureVisitor::VisitFunctionTemplateDecl(FunctionTemplateDecl *decl)
 {
   Closure.Add_Decl_And_Prevs(decl);

diff --git a/libcextract/Closure.hh b/libcextract/Closure.hh
@@ -189,6 +189,8 @@ class DeclClosureVisitor : public RecursiveASTVisitor<DeclClosureVisitor>
 
   bool VisitVarDecl(VarDecl *decl);
 
+  bool VisitNamedDecl(NamedDecl *decl);
+
   /* --------- C++ Declarations ---------- */
 
   bool VisitFunctionTemplateDecl(FunctionTemplateDecl *decl);

diff --git a/testsuite/small/c++-linkage-4.cpp b/testsuite/small/c++-linkage-4.cpp
@@ -0,0 +1,24 @@
+/* { dg-options "-DCE_EXTRACT_FUNCTIONS=main -DCE_NO_EXTERNALIZATION" }*/
+/* { dg-xfail }*/
+
+typedef unsigned long size_t;
+typedef int unused_t;
+
+extern "C++" {
+namespace std
+{
+  enum class align_val_t: size_t {};
+  unsigned int unused;
+
+};
+};
+
+std::align_val_t f(void)
+{
+  std::align_val_t r;
+  return r;
+}
+
+/* { dg-final { scan-tree-dump "enum class align_val_t: size_t" } } */
+/* { dg-final { scan-tree-dump-not "unused_t" } } */
+/* { dg-final { scan-tree-dump-not "unused" } } */