)]}'
{
  "commit": "1d45d90934b10862c00a22bcf4075815a785001b",
  "tree": "64ac6a72a23c6192d45cdac5d9c8621c2e4195c5",
  "parents": [
    "5d4a870e05ac45e3f5a301c672a4079995b5db7a"
  ],
  "author": {
    "name": "Tom de Vries",
    "email": "tdevries@suse.de",
    "time": "Mon Oct 16 16:32:28 2023 +0200"
  },
  "committer": {
    "name": "Tom de Vries",
    "email": "tdevries@suse.de",
    "time": "Mon Oct 16 16:32:28 2023 +0200"
  },
  "message": "[gdb/symtab] Work around PR gas/29517\n\nWhen using glibc debuginfo generated with gas 2.39, we run into PR gas/29517:\n...\n$ gdb -q -batch a.out -ex start -ex \"p (char *)strstr (\\\"haha\\\", \\\"ah\\\")\"\nTemporary breakpoint 1 at 0x40051b: file hello.c, line 6.\n\nTemporary breakpoint 1, main () at hello.c:6\n6\t  printf (\"hello\\n\");\nInvalid cast.\n...\nwhile without glibc debuginfo installed we get the expected result:\n...\n$n \u003d 0x7ffff7daa1b1 \"aha\"\n...\nand likewise with glibc debuginfo generated with gas 2.40.\n\nThe strstr ifunc resolves to __strstr_sse2_unaligned.  The problem is that gas\ngenerates dwarf that states that the return type is void:\n...\n\u003c1\u003e\u003c3e1e58\u003e: Abbrev Number: 2 (DW_TAG_subprogram)\n    \u003c3e1e59\u003e   DW_AT_name        : __strstr_sse2_unaligned\n    \u003c3e1e5d\u003e   DW_AT_external    : 1\n    \u003c3e1e5e\u003e   DW_AT_low_pc      : 0xbbd2e\n    \u003c3e1e66\u003e   DW_AT_high_pc     : 0xbc1c3\n...\nwhile the return type should be a DW_TAG_unspecified_type, as is the case\nwith gas 2.40.\n\nWe can still use the workaround of casting to another function type for both\n__strstr_sse2_unaligned:\n...\n(gdb) p ((char * (*) (const char *, const char *))__strstr_sse2_unaligned) \\\n  (\"haha\", \"ah\")\n$n \u003d 0x7ffff7daa211 \"aha\"\n...\nand strstr (which requires using *strstr to dereference the ifunc before we\ncast):\n...\ngdb) p ((char * (*) (const char *, const char *))*strstr) (\"haha\", \"ah\")\n$n \u003d 0x7ffff7daa251 \"aha\"\n...\nbut that\u0027s a bit cumbersome to use.\n\nWork around this in the dwarf reader, such that we have instead:\n...\n(gdb) p (char *)strstr (\"haha\", \"ah\")\n$n \u003d 0x7ffff7daa1b1 \"aha\"\n...\n\nThis also requires fixing producer_is_gcc to stop returning true for\nproducer \"GNU AS 2.39.0\".\n\nTested on x86_64-linux.\n\nApproved-By: Andrew Burgess \u003caburgess@redhat.com\u003e\n\nPR symtab/30911\nBug: https://sourceware.org/bugzilla/show_bug.cgi?id\u003d30911\n",
  "tree_diff": [
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