bug#53358: 29.0.50; Compilation output messed up again

[Paul Eggert <eggert@cs.ucla.edu>]

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On 1/21/22 01:24, Lars Ingebrigtsen wrote:
> I see it on every build I do (8 core machine, 16 threads, so I use
> -j16).

Ah, your machine is beefier than mine.

I installed the attached to attempt to implement your suggestion to use 
an 'echo' workaround only for "ELC"-like lines. Please give it a try.

The workaround is used only for current (and older) versions of GNU 
Make, so it will phase itself out eventually. In the meantime I can use 
bleeding-edge Make to debug without worrying about the extra processes 
generated by the 'echo' approach.

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From 882bbeb1f9f40ccf9f1e3f3423fd7cb12a4859ab Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Fri, 21 Jan 2022 13:33:55 -0800
Subject: [PATCH 1/2] Simplify AM_V_ELC setup
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

* src/verbose.mk.in (AM_V_ELC, AM_V_ELN): Use simpler Make ‘if’s.
---
 src/verbose.mk.in | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/src/verbose.mk.in b/src/verbose.mk.in
index 01076df946..c0bf67abd4 100644
--- a/src/verbose.mk.in
+++ b/src/verbose.mk.in
@@ -39,23 +39,13 @@ AM_V_CC      = @$(info $   CC       $@)
 AM_V_CXX     = @$(info $   CXX      $@)
 AM_V_CCLD    = @$(info $   CCLD     $@)
 AM_V_CXXLD   = @$(info $   CXXLD    $@)
-ifeq ($(HAVE_NATIVE_COMP),yes)
-ifneq ($(NATIVE_DISABLED),1)
-ifneq ($(ANCIENT),yes)
+ifeq ($(HAVE_NATIVE_COMP)-$(NATIVE_DISABLED)-$(ANCIENT),yes--)
 AM_V_ELC     = @$(info $   ELC+ELN  $@)
 AM_V_ELN     = @$(info $   ELN      $@)
 else
 AM_V_ELC     = @$(info $   ELC      $@)
 AM_V_ELN =
 endif
-else
-AM_V_ELC     = @$(info $   ELC      $@)
-AM_V_ELN =
-endif
-else
-AM_V_ELC     = @$(info $   ELC      $@)
-AM_V_ELN =
-endif
 AM_V_GEN     = @$(info $   GEN      $@)
 AM_V_GLOBALS = @$(info $   GEN      globals.h)
 AM_V_NO_PD = --no-print-directory
-- 
2.32.0


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From fac8d0ac2f4cbdbd5828a57ddc90adf6601d956b Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Fri, 21 Jan 2022 14:45:57 -0800
Subject: [PATCH 2/2] Avoid glitches in ELC lines in build output

* src/verbose.mk.in (have_working_info): New macro.
(AM_V_ELC, AM_V_ELN): Use 'echo' rather than $(info ...)
on buggy versions of GNU Make.
---
 src/verbose.mk.in | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/src/verbose.mk.in b/src/verbose.mk.in
index c0bf67abd4..eb99e42695 100644
--- a/src/verbose.mk.in
+++ b/src/verbose.mk.in
@@ -33,19 +33,45 @@ AM_V_GLOBALS =
 AM_V_NO_PD =
 AM_V_RC =
 else
+
+# Whether $(info ...) works.  This is to work around a bug in GNU Make
+# 4.3 and earlier, which implements $(info MSG) via two system calls
+# { write (..., "MSG", 3); write (..., "\n", 1); }
+# which looks bad when make -j interleaves two of these at about the same time.
+#
+# Later versions of GNU Make have the 'notintermediate' feature,
+# so assume that $(info ...) works if this feature is present.
+#
+have_working_info = $(filter notintermediate,$(value .FEATURES))
+#
+# The workaround is to use the shell and 'echo' rather than $(info ...).
+# The workaround is done only for AM_V_ELC and AM_V_ELN,
+# since the bug is not annoying elsewhere.
+
 AM_V_AR      = @$(info $   AR       $@)
 AM_V_at = @
 AM_V_CC      = @$(info $   CC       $@)
 AM_V_CXX     = @$(info $   CXX      $@)
 AM_V_CCLD    = @$(info $   CCLD     $@)
 AM_V_CXXLD   = @$(info $   CXXLD    $@)
+
 ifeq ($(HAVE_NATIVE_COMP)-$(NATIVE_DISABLED)-$(ANCIENT),yes--)
+ifdef have_working_info
 AM_V_ELC     = @$(info $   ELC+ELN  $@)
 AM_V_ELN     = @$(info $   ELN      $@)
 else
+AM_V_ELC     = @echo "  ELC+ELN " $@;
+AM_V_ELN     = @echo "  ELN     " $@;
+endif
+else
+ifdef have_working_info
 AM_V_ELC     = @$(info $   ELC      $@)
+else
+AM_V_ELC     = @echo "  ELC     " $@;
+endif
 AM_V_ELN =
 endif
+
 AM_V_GEN     = @$(info $   GEN      $@)
 AM_V_GLOBALS = @$(info $   GEN      globals.h)
 AM_V_NO_PD = --no-print-directory
-- 
2.32.0