From 078c68a2e5f04331bf53d3cdee2cffe031056154 Mon Sep 17 00:00:00 2001
From: Samuel Debionne <samuel.debionne@gmail.com>
Date: Sat, 29 May 2021 02:55:04 +0200
Subject: [PATCH] Add default value for cxx and cxxflags options for the cxx
 toolset (#24)

Add default value for cxx and cxxflags options for the cxx toolset
---
 src/engine/build.sh | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/engine/build.sh b/src/engine/build.sh
index 1a9f8c8a7..b36573b02 100755
--- a/src/engine/build.sh
+++ b/src/engine/build.sh
@@ -276,12 +276,19 @@ if test_true ${B2_HELP_OPT} ; then
     error_exit
 fi
 
-# If we have a CXX but no B2_TOLSET specified by the user we assume they meant
+# If we have a CXX but no B2_TOOLSET specified by the user we assume they meant
 # "cxx" as the toolset.
 if test "${B2_CXX_OPT}" != "" -a "${B2_TOOLSET}" = "" ; then
     B2_TOOLSET=cxx
 fi
 
+# If we have B2_TOOLSET=cxx but no B2_CXX_OPT nor B2_CXXFLAGS_OPT specified by the user
+# we assume they meant $CXX and $CXXFLAGS.
+if test "${B2_TOOLSET}" = "cxx" -a "${B2_CXX_OPT}" = "" -a "${B2_CXXFLAGS_OPT}" = "" ; then
+    B2_CXX_OPT="${CXX}"
+    B2_CXXFLAGS_OPT="${CXXFLAGS}"
+fi
+
 # Guess toolset, or toolset commands.
 check_toolset
 TOOLSET_CHECK=$?