Re: [PATCH v1 3/6] perf symbol: Move demangling code out of symbol-elf.c

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Tue, May 27, 2025 at 11:07:00AM -0700, Ian Rogers wrote:
> symbol-elf.c is used when building with libelf, symbol-minimal is used
> otherwise. There is no reason the demangling code with no dependencies
> on libelf is part of symbol-elf.c so move to symbol.c. This allows
> demangling tests to pass with NO_LIBELF=1.

At this point:

⬢ [acme@toolbx perf-tools-next]$ alias m='rm -rf ~/libexec/perf-core/ ; make -k O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin && perf test python && cat /tmp/build/$(basename $PWD)/feature/test-all.make.output'
⬢ [acme@toolbx perf-tools-next]$ m
rm: cannot remove '/home/acme/libexec/perf-core/scripts/python/Perf-Trace-Util/lib/Perf/Trace/__pycache__/Core.cpython-313.pyc': Permission denied
make: Entering directory '/home/acme/git/perf-tools-next/tools/perf'
  BUILD:   Doing 'make -j32' parallel build
Warning: Kernel ABI header differences:
  diff -u tools/arch/arm64/include/asm/cputype.h arch/arm64/include/asm/cputype.h

Auto-detecting system features:
...                                   libdw: [ on  ]
...                                   glibc: [ on  ]
...                                  libelf: [ on  ]
...                                 libnuma: [ on  ]
...                  numa_num_possible_cpus: [ on  ]
...                                 libperl: [ on  ]
...                               libpython: [ on  ]
...                               libcrypto: [ on  ]
...                             libcapstone: [ on  ]
...                               llvm-perf: [ on  ]
...                                    zlib: [ on  ]
...                                    lzma: [ on  ]
...                               get_cpuid: [ on  ]
...                                     bpf: [ on  ]
...                                  libaio: [ on  ]
...                                 libzstd: [ on  ]

  INSTALL libsubcmd_headers
  INSTALL libperf_headers
  INSTALL libapi_headers
  INSTALL libsymbol_headers
  INSTALL libbpf_headers
  AR      /tmp/build/perf-tools-next/libpmu-events.a
  CC      /tmp/build/perf-tools-next/util/symbol-elf.o
util/symbol-elf.c: In function ‘get_plt_got_name’:
util/symbol-elf.c:563:21: error: implicit declaration of function ‘demangle_sym’; did you mean ‘dso__demangle_sym’? [-Wimplicit-function-declaration]
  563 |         demangled = demangle_sym(di->dso, 0, sym_name);
      |                     ^~~~~~~~~~~~
      |                     dso__demangle_sym
util/symbol-elf.c:563:19: error: assignment to ‘char *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
  563 |         demangled = demangle_sym(di->dso, 0, sym_name);
      |                   ^
util/symbol-elf.c: In function ‘dso__synthesize_plt_symbols’:
util/symbol-elf.c:761:27: error: assignment to ‘char *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
  761 |                 demangled = demangle_sym(dso, 0, elf_name);
      |                           ^
util/symbol-elf.c: In function ‘dso__load_sym_internal’:
util/symbol-elf.c:1778:27: error: assignment to ‘char *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
 1778 |                 demangled = demangle_sym(dso, kmodule, elf_name);
      |                           ^
make[4]: *** [/home/acme/git/perf-tools-next/tools/build/Makefile.build:85: /tmp/build/perf-tools-next/util/symbol-elf.o] Error 1
make[3]: *** [/home/acme/git/perf-tools-next/tools/build/Makefile.build:142: util] Error 2
make[2]: *** [Makefile.perf:798: /tmp/build/perf-tools-next/perf-util-in.o] Error 2
make[1]: *** [Makefile.perf:290: sub-make] Error 2
make: *** [Makefile:119: install-bin] Error 2
make: Leaving directory '/home/acme/git/perf-tools-next/tools/perf'
⬢ [acme@toolbx perf-tools-next]$

- Arnaldo