From 2615ebca43af2c147522a31c50287d81c4b44008 Mon Sep 17 00:00:00 2001
From: "Wladimir J. van der Laan" <laanwj@gmail.com>
Date: Wed, 13 Jun 2018 15:46:46 +0200
Subject: [PATCH] Merge #13445: build: Reset default -g -O2 flags when enable
 debug

9882d1f044133832b3c0809676d5f26a861b9f44 Reset default -g -O2 flags when enable debug (Chun Kuan Lee)

Pull request description:

  The default CXXFLAGS is -g -O2, this should not appear when enable debug.
  fixes #13432

Tree-SHA512: 79447f3e1fab9e6cd12f5ca49b3d42187e856e0c159ed01140ea93d6ef1fbb1af3d65b338308566330491052c0177d12abe26796513502ddde31692665a0dbb4
---
 configure.ac | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/configure.ac b/configure.ac
index c727c67563..c113627762 100644
--- a/configure.ac
+++ b/configure.ac
@@ -281,6 +281,10 @@ AC_LANG_PUSH([C++])
 AX_CHECK_COMPILE_FLAG([-Werror],[CXXFLAG_WERROR="-Werror"],[CXXFLAG_WERROR=""])
 
 if test "x$enable_debug" = xyes; then
+  # Clear default -g -O2 flags
+  if test "x$CXXFLAGS_overridden" = xno; then
+	CXXFLAGS=""
+  fi
   # Prefer -Og, fall back to -O0 if that is unavailable.
   AX_CHECK_COMPILE_FLAG(
     [-Og],