From 123f165013c6a923e3b47422e09f456ab24a28e9 Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@redhat.com>
Date: Fri, 14 Dec 2018 19:30:10 +0100
Subject: [PATCH] bpo-35499: make profile-opt don't override CFLAGS_NODIST

"make profile-opt" no longer replaces CFLAGS_NODIST with CFLAGS. It
now adds profile-guided optimization (PGO) flags to CFLAGS_NODIST,
existing CFLAGS_NODIST flags are kept.
---
 Makefile.pre.in                                               | 4 ++--
 .../next/Build/2018-12-14-19-36-05.bpo-35499.9yAldM.rst       | 3 +++
 2 files changed, 5 insertions(+), 2 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Build/2018-12-14-19-36-05.bpo-35499.9yAldM.rst

diff --git a/Makefile.pre.in b/Makefile.pre.in
index f16eb96418e97b..9c790f1bc60b3e 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -496,7 +496,7 @@ profile-run-stamp:
 	touch $@
 
 build_all_generate_profile:
-	$(MAKE) @DEF_MAKE_RULE@ CFLAGS_NODIST="$(CFLAGS) $(PGO_PROF_GEN_FLAG)" LDFLAGS="$(LDFLAGS) $(PGO_PROF_GEN_FLAG)" LIBS="$(LIBS)"
+	$(MAKE) @DEF_MAKE_RULE@ CFLAGS_NODIST="$(CFLAGS_NODIST) $(PGO_PROF_GEN_FLAG)" LDFLAGS="$(LDFLAGS) $(PGO_PROF_GEN_FLAG)" LIBS="$(LIBS)"
 
 run_profile_task:
 	@ # FIXME: can't run for a cross build
@@ -510,7 +510,7 @@ build_all_merge_profile:
 profile-opt: profile-run-stamp
 	@echo "Rebuilding with profile guided optimizations:"
 	-rm -f profile-clean-stamp
-	$(MAKE) @DEF_MAKE_RULE@ CFLAGS_NODIST="$(CFLAGS) $(PGO_PROF_USE_FLAG)" LDFLAGS="$(LDFLAGS)"
+	$(MAKE) @DEF_MAKE_RULE@ CFLAGS_NODIST="$(CFLAGS_NODIST) $(PGO_PROF_USE_FLAG)" LDFLAGS="$(LDFLAGS)"
 
 # Compile and run with gcov
 .PHONY=coverage coverage-lcov coverage-report
diff --git a/Misc/NEWS.d/next/Build/2018-12-14-19-36-05.bpo-35499.9yAldM.rst b/Misc/NEWS.d/next/Build/2018-12-14-19-36-05.bpo-35499.9yAldM.rst
new file mode 100644
index 00000000000000..ed730b9d9b4a49
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2018-12-14-19-36-05.bpo-35499.9yAldM.rst
@@ -0,0 +1,3 @@
+``make profile-opt`` no longer replaces ``CFLAGS_NODIST`` with ``CFLAGS``. It
+now adds profile-guided optimization (PGO) flags to ``CFLAGS_NODIST``: existing
+``CFLAGS_NODIST`` flags are kept.