Comment #3 on issue 43505 by evv...@gmail.com: elfutils:fuzz-dwfl-core: 
Use-of-uninitialized-value in handle_file_note
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=43505#c3

Looking at another issue that hasn't been reported by OSS-Fuzz yet:
```
        Running: 
/mnt/scratch0/clusterfuzz/bot/inputs/fuzzer-testcases/crash-57876e6ee0a1504e6fa0b22336043846f283f4a2
==742==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x6374a5 in dwfl_segment_report_module 
/src/elfutils/libdwfl/dwfl_segment_report_module.c:401:11
    #1 0x537d0d in dwfl_core_file_report 
/src/elfutils/libdwfl/core-file.c:563:17
    #2 0x528aa5 in LLVMFuzzerTestOneInput /src/fuzz-dwfl-core.c:52:6
    #3 0x455243 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, 
unsigned long) cxa_noexception.cpp:0
    #4 0x440e92 in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned 
long) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:324:6
    #5 0x4466dc in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char 
const*, unsigned long)) cxa_noexception.cpp:0
    #6 0x46f4a2 in main 
/src/llvm-project/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10
    #7 0x7f5d0ddbc0b2 in __libc_start_main 
/build/glibc-eX1tMB/glibc-2.31/csu/libc-start.c:308:16
    #8 0x41f60d in _start
  Uninitialized value was created by an allocation of 'ehdr' in the stack frame 
of function 'dwfl_segment_report_module'
    #0 0x62d610 in dwfl_segment_report_module 
/src/elfutils/libdwfl/dwfl_segment_report_module.c:301
```

it seems MSan doesn't like unions that aren't initialized explicitly

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