[all-commits] [llvm/llvm-project] e6e61e: Revert "Reapply: Add an error message to the defau...

[Bill Wendling via All-commits]

  Branch: refs/heads/release/15.x
  Home:   https://github.com/llvm/llvm-project
  Commit: e6e61e9b2ef7c0fa3fe2cd7c612e00ecf57a9dd8
      https://github.com/llvm/llvm-project/commit/e6e61e9b2ef7c0fa3fe2cd7c612e00ecf57a9dd8
  Author: Bill Wendling <morbo at google.com>
  Date:   2022-11-23 (Wed, 23 Nov 2022)

  Changed paths:
    M llvm/lib/Support/Unix/Signals.inc
    R llvm/test/Support/unix03-sigpipe-exit.test

  Log Message:
  -----------
  Revert "Reapply: Add an error message to the default SIGPIPE handler"

This patch is spamming compiles with unhelpful and confusing messages.
E.g. the Linux kernel uses "grep -q" in several places. It's meant to
quit with a return code of zero when the first match is found. This can
cause a SIGPIPE signal, but that's expected, and there's no way to turn
this error message off to avoid spurious error messages.

UNIX03 apparently doesn't require printing an error message on SIGPIPE,
but specifically when there's an error on the stdout stream in a normal
program flow, e.g. when SIGPIPE trap is disabled.

A separate patch is planned to address the specific case we care most
about (involving llvm-nm).

This reverts commit b89bcefa6202e310eb3167dd1c37f1807377ec8d.

Link: https://github.com/llvm/llvm-project/issues/59037
Link: https://github.com/ClangBuiltLinux/linux/issues/1651

Differential Revision: https://reviews.llvm.org/D138244

(cherry picked from commit 4787efa38066adb51e2c049499d25b3610c0877b)