[PATCH] D85116: [compiler-rt][profile] Fix various InstrProf tests on Solaris

Mon Aug 24 08:19:18 PDT 2020

inferno added a comment.

First, how did you verify that this patch is the culprit? While it seems plausible, I've seen too many cases where a likely candidate turned out to be innocent, wasting everyone's time.

When chromium folks were rolling clang, it was the only suspect in code coverage changes - llvmorg-12-init-1771-g1bd7046e : llvmorg-12-init-3492-ga1caa302 [like git hash, these are tags, git checkout to them work ]

Can you please also provide lots of additional information:

Which platform are you seeing this error on?

Seen on linux. See red ones on https://oss-fuzz-build-logs.storage.googleapis.com/index.html#curl [for now, i had to hardcode a older clang commit]

Which revision of clang were you using? Any local changes? How exactly was cmake invoked?

https://github.com/google/oss-fuzz/blob/master/infra/base-images/base-clang/checkout_build_install_llvm.sh

Which linker do you use?

System linker on ubuntu 16.04 inside docker. GNU ld (GNU Binutils for Ubuntu) 2.26.1

Can you provide the output of readelf -SW for the binary that produces the error, the version of libclang_rt.profile-*.alinked, and if possible for the input objects that have __llvm_prf_names sections?

libclang_rt.profile-x86_64.a

readelf -SW curl_fuzzer_ldap
============================

There are 48 section headers, starting at offset 0xdc56e8:

Section Headers:

  [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
  [ 1] .interp           PROGBITS        0000000000400270 000270 00001c 00   A  0   0  1
  [ 2] .note.ABI-tag     NOTE            000000000040028c 00028c 000020 00   A  0   0  4
  [ 3] .gnu.hash         GNU_HASH        00000000004002b0 0002b0 0003d8 00   A  4   0  8
  [ 4] .dynsym           DYNSYM          0000000000400688 000688 0026a0 18   A  5   1  8
  [ 5] .dynstr           STRTAB          0000000000402d28 002d28 001a18 00   A  0   0  1
  [ 6] .gnu.version      VERSYM          0000000000404740 004740 000338 02   A  4   0  2
  [ 7] .gnu.version_r    VERNEED         0000000000404a78 004a78 000180 00   A  5   7  8
  [ 8] .rela.dyn         RELA            0000000000404bf8 004bf8 0003f0 18   A  4   0  8
  [ 9] .rela.plt         RELA            0000000000404fe8 004fe8 001980 18  AI  4  28  8
  [10] .init             PROGBITS        0000000000406968 006968 00001f 00  AX  0   0  4
  [11] .plt              PROGBITS        0000000000406990 006990 001110 10  AX  0   0 16
  [12] .plt.got          PROGBITS        0000000000407aa0 007aa0 000068 00  AX  0   0  8
  [13] .text             PROGBITS        0000000000407c00 007c00 30c58f 00  AX  0   0 256
  [14] .fini             PROGBITS        0000000000714190 314190 000009 00  AX  0   0  4
  [15] .rodata           PROGBITS        0000000000715000 315000 0adb73 00   A  0   0 4096
  [16] __llvm_prf_names  PROGBITS        00000000007c2b73 3c2b73 02ac61 00   A  0   0  1
  [17] .eh_frame_hdr     PROGBITS        00000000007ed7d4 3ed7d4 01383c 00   A  0   0  4
  [18] .eh_frame         PROGBITS        0000000000801010 401010 0656e4 00   A  0   0  8
  [19] .gcc_except_table PROGBITS        00000000008666f4 4666f4 0003a8 00   A  0   0  4
  [20] .tbss             NOBITS          0000000000a67590 467590 000038 00 WAT  0   0  8
  [21] .preinit_array    PREINIT_ARRAY   0000000000a67590 467590 000010 00  WA  0   0  8
  [22] .init_array       INIT_ARRAY      0000000000a675a0 4675a0 000030 00  WA  0   0  8
  [23] .fini_array       FINI_ARRAY      0000000000a675d0 4675d0 000008 00  WA  0   0  8
  [24] .jcr              PROGBITS        0000000000a675d8 4675d8 000008 00  WA  0   0  8
  [25] .data.rel.ro      PROGBITS        0000000000a675e0 4675e0 00a698 00  WA  0   0 16
  [26] .dynamic          DYNAMIC         0000000000a71c78 471c78 000250 10  WA  5   0  8
  [27] .got              PROGBITS        0000000000a71ec8 471ec8 000138 08  WA  0   0  8
  [28] .got.plt          PROGBITS        0000000000a72000 472000 000898 08  WA  0   0  8
  [29] .data             PROGBITS        0000000000a728a0 4728a0 014cd8 00  WA  0   0 16
  [30] __llvm_prf_cnts   PROGBITS        0000000000a87578 487578 0766c0 00  WA  0   0  8
  [31] __llvm_prf_data   PROGBITS        0000000000afdc38 4fdc38 057f60 00  WA  0   0  8
  [32] __llvm_prf_vnds   PROGBITS        0000000000b55ba0 555ba0 006000 00  WA  0   0 16
  [33] .bss              NOBITS          0000000000b5bc00 55bba0 94cf10 00  WA  0   0 512
  [34] .comment          PROGBITS        0000000000000000 55bba0 00009e 01  MS  0   0  1
  [35] .deplibs          LOOS+fff4c04    0000000000000000 55bc3e 00000b 01  MS  0   0  1
  [36] __llvm_covfun     PROGBITS        0000000000000000 55bc50 252b95 00      0   0  8
  [37] __llvm_covmap     PROGBITS        0000000000000000 7ae7e8 01b6e0 00      0   0  8
  [38] .debug_aranges    PROGBITS        0000000000000000 7c9ec8 0004f0 00      0   0  1
  [39] .debug_info       PROGBITS        0000000000000000 7ca3b8 245d9a 00      0   0  1
  [40] .debug_abbrev     PROGBITS        0000000000000000 a10152 019e15 00      0   0  1
  [41] .debug_line       PROGBITS        0000000000000000 a29f67 163fa0 00      0   0  1
  [42] .debug_str        PROGBITS        0000000000000000 b8df07 0371eb 01  MS  0   0  1
  [43] .debug_loc        PROGBITS        0000000000000000 bc50f2 085fcd 00      0   0  1
  [44] .debug_ranges     PROGBITS        0000000000000000 c4b0bf 056450 00      0   0  1
  [45] .shstrtab         STRTAB          0000000000000000 dc54fc 0001ec 00      0   0  1
  [46] .symtab           SYMTAB          0000000000000000 ca1510 084ae0 18     47 7588  8
  [47] .strtab           STRTAB          0000000000000000 d25ff0 09f50c 00      0   0  1

Key to Flags:

  W (write), A (alloc), X (execute), M (merge), S (strings), l (large)
  I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
  O (extra OS processing required) o (OS specific), p (processor specific)

I dont know how to get __llvm_prf_names section

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D85116/new/

https://reviews.llvm.org/D85116