[rootcling] Remove check for unique_ptr members#20389
Merged
hahnjo merged 2 commits intoroot-project:masterfrom Nov 12, 2025
Merged
[rootcling] Remove check for unique_ptr members#20389hahnjo merged 2 commits intoroot-project:masterfrom
unique_ptr members#20389hahnjo merged 2 commits intoroot-project:masterfrom
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Since llvm/llvm-project@f5e687d libc++ implements _LIBCPP_COMPRESSED_PAIR with an anonymous struct (a Clang extension). This results in unique_ptr having a single FieldDecl with an empty name that does not appear as a data member in TClass. Instead, the AST has multiple IndirectFieldDecl's that "refer" into the anonymous struct. In ROOT, we now have two options: We could support anonymous structs, either by allowing data members with empty names or by adding all indirect field declarations as members. However, I would argue that we actually do NOT want to support this extension for IO classes. Instead remove the (questionable) check in rootcling that verifies the number of data members in unique_ptr.
Since the previous commit, IsUnsupportedUniquePointer does not check the number of data members anymore.
pcanal
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Nov 12, 2025
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Thanks for the investigation.
We could support anonymous structs, either by allowing data members with empty names or by adding all indirect field declarations as members. However, I would argue that we actually do NOT want to support this extension for IO classes.
We should probably (also) document/memorialize that we do not support this case (i.e. it 'could' affect some user code).
Side note that the real/essential check is already done by IsUniquePtrOffsetZero (i.e. support for unique_ptr requires that it is (strictly) using the same memory layout as a raw pointer).
Test Results 22 files 22 suites 3d 23h 23m 12s ⏱️ Results for commit 10fa16d. |
This was referenced Nov 12, 2025
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Since llvm/llvm-project@f5e687d libc++ implements
_LIBCPP_COMPRESSED_PAIRwith an anonymous struct (a Clang extension). This results inunique_ptrhaving a singleFieldDeclwith an empty name that does not appear as a data member inTClass. Instead, the AST has multipleIndirectFieldDecls that "refer" into the anonymous struct.In ROOT, we now have two options: We could support anonymous structs, either by allowing data members with empty names or by adding all indirect field declarations as members. However, I would argue that we actually do NOT want to support this extension for IO classes. Instead remove the (questionable) check in
rootclingthat verifies the number of data members inunique_ptr.Closes #20377