util: remove unused exception parameter in Popen::execute_process

[fanquake]

[451/1129] Building CXX object src/CMakeFiles/bitcoin_common.dir/common/run_command.cpp.o
In file included from ../src/common/run_command.cpp:10:
../src/util/subprocess.h:1219:30: warning: unused exception parameter 'exp' [-Wunused-exception-parameter]
 1219 |     } catch (std::exception& exp) {
      |                              ^~~
1 warning generated.

Related to #36167.

[DrahtBot]

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Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/36383.

Reviews

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Type	Reviewers
ACK	musaHaruna, maflcko, willcl-ark, hebasto

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #36167 ([RFC] Enable -Wunused by fanquake)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

[fanquake]

Upstreamed in arun11299/cpp-subprocess#133.

[musaHaruna]

ACK cde2f2e

Checked that removing exp leaves the catch type, cleanup call, and throw; unchanged.

Built on macOS arm64 with Apple Clang 17, with -Wunused-exception-parameter and -Werror enabled. Confirmed the original header triggers the warning and the updated header compiles successfully.

[maflcko]

Built on macOS arm64 with Apple Clang 17

Unrelated, but I see you are compiling with Apple Clang 17. I wonder which exact version, because in #36287 I bump to the latest Apple Clang 17 version. So I wonder if this works for you, or if you'd have to upgrade your macOS and/or XCode.

[maflcko]

lgtm ACK cde2f2e

Seems fine to enforce this as a small, mostly-style preference.

[musaHaruna]

Unrelated, but I see you are compiling with Apple Clang 17. I wonder which exact version, because in #36287 I bump to the latest Apple Clang 17 version. So I wonder if this works for you, or if you'd have to upgrade your macOS and/or XCode.

I’m using Apple Clang 17.0.0 (clang-1700.6.3.2) from Command Line Tools 26.2, on macOS 26.0 (arm64). I haven't looked at #36287 yet, but I will take a look.

[willcl-ark]

ACK cde2f2e

[hebasto]

ACK cde2f2e.