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Marchesi wrote: > > We agreed in the meeting to implement Solution 2 below in both GCC and > clang. > > The DW_TAG_LLVM_annotation DIE number will be changed in order to make > it possible for pahole to handle the current tags. The number of the > new tag will be shared by both GCC and clang. w.r.t c2x attribute syntax discussion in 01/19 office hour discussion. I have checked clang c2x syntax w.r.t. btf_type_tag and btf_decl_tag. They are both supported with clang 15 and 16. See: https://clang.llvm.org/docs/AttributeReference.html The c2x btf_decl_tag attr syntax is [[clang::btf_decl_tag("")]]. The c2x btf_type_tag attr syntax is [[clang::btf_type_tag("")]]. $ cat t.c int [[clang::btf_type_tag("aa")]] * [[clang::btf_type_tag("bb")]] *f; [[clang::btf_decl_tag("cc")]] int foo() { return 5; } int bar() { return foo(); } $ clang -std=c2x -g -O2 -c t.c $ llvm-dwarfdump t.o | grep btf | grep tag DW_AT_name ("btf_type_tag") DW_AT_name ("btf_type_tag") DW_AT_name ("btf_decl_tag") I double checked and the c2x syntax above generates the *same* type IR and dwarf compared to __attribute__ style attributes. [...]