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SimonKagstrom / kcov

Code coverage tool for compiled programs, Python and Bash which uses debugging information to collect and report data without special compilation options
http://simonkagstrom.github.io/kcov/
GNU General Public License v2.0
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Allow a single address to map to multiple lines #366

Closed dsteeley closed 2 years ago

dsteeley commented 2 years ago

kcov currently only allows an address to be mapped to a single line.

Rust produces coverage information of the form:

[root@9cc0f19f33ac default_ignore]# readelf --debug-dump=decodedline target/debug/default_ignore-addf76c983f37444 | grep -A 20 "CU: src/lib.rs"
CU: src/lib.rs:
File name                            Line number    Starting address
lib.rs                                         8             0x1e480
lib.rs                                        10             0x1e480

kcov reads this information for lib.rs:8, and gets the mapping for 0x1e480 and creates a mapping and life is good.

It then reads the information for lib.rs:10 and gets the mapping for 0x1e480, and overwrites the mapping for lib.rs:8 (leaking it in the process), and life is now not good.

To resolve this, I've tweaked kcov, so that it's address mapping is now a std::map<uint64_t, std::vector<Line*>> instead of just being a std::map<uint64_t, Line*>.

SimonKagstrom commented 2 years ago

Again, awfully sorry for letting this "rust" for over a month. Thanks a lot for your very nice debugging, investigation and implementation!

SimonKagstrom commented 2 years ago

I'm investigating a problem with the bash tests caused by these commits, but I'll fix that issue.

SimonKagstrom commented 2 years ago

The bash issue has been fixed with 652409e, but it would be good to get confirmation that it doesn't break the intended fix for Rust (and maybe other targets?).