This PR adds troubleshooting information to explain how to overcome two errors that may arise when running the tests with coverage as described in doc/developer-notes.md.
Specifically, running the cmake -P build/Coverage.cmake step may produce geninfo mismatch errors of the following sort (Ubuntu 24.04, GNU 13.3.0 compiler, LCOV version 2.0-1):
$ cmake -B build -DCMAKE_BUILD_TYPE=Coverage
$ cmake --build build
$ cmake -P build/Coverage.cmake
geninfo: ERROR: mismatched end line for _ZN7Num30723SerI10DataStreamEEvRT_RKS_ at /home/espi3/src/bitcoin/src/crypto/muhash.h:62: 67 -> 62
(use "geninfo --ignore-errors mismatch ..." to bypass this error)
CMake Error at build/CoverageInclude.cmake:45 (execute_process):
execute_process failed command indexes:
1: "Child return code: 1"
Call Stack (most recent call first):
build/Coverage.cmake:5 (include)
This may be due to multiline macros such as SERIALIZE_METHODS, so I would expect others to run into the same issue.
Additionally, after suppressing the mismatch errors, I get a geninfo negative count error:
geninfo: ERROR: Unexpected negative count '-185' for /home/espi3/src/bitcoin/src/secp256k1/src/field_5x52_impl.h:183.
Perhaps you need to compile with '-fprofile-update=atomic
(use "geninfo --ignore-errors negative ..." to bypass this error)
CMake Error at build/Coverage.cmake:21 (execute_process):
execute_process failed command indexes:
1: "Child return code: 1"
I don't know the cause, and don't yet know enough C++ to investigate it properly. This PR takes the approach of describing a workaround.
