cmd/compile/internal/gc: handle errors from *bio.Writer

[mateusz834]

The error is stored internally in *bio.Writer, more specifically
in *bufio.Writer and the current code does not handle it, ignoring
errors silently.

[gopherbot]

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Mateusz Poliwczak:

Patch Set 2: Commit-Queue+1

(1 comment)

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[gopherbot]

Message from Go LUCI:

Patch Set 2:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2025-02-08T14:02:57Z","revision":"1b75be157cd1099a523c6eb65d0be2575750546c"}

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Message from Mateusz Poliwczak:

Patch Set 2: -Commit-Queue

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Message from Go LUCI:

Patch Set 2:

This CL has passed the run

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Message from Go LUCI:

Patch Set 2: LUCI-TryBot-Result+1

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Message from Keith Randall:

Patch Set 2: Auto-Submit+1 Code-Review+2

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Message from Keith Randall:

Patch Set 2: Code-Review+1

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[gopherbot]

This PR is being closed because golang.org/cl/647915 has been merged.