Makefile.am and configure.ac: setting default CXXFLAGS in the right place

Author: andrewdavidsmith

Makefile.am

@@ -19,7 +19,8 @@ EXTRA_DIST = README.md LICENSE Configuration example.fq test
 ACLOCAL_AMFLAGS = -I m4
 AM_CPPFLAGS = -I $(top_srcdir)/src
 
-CXXFLAGS = -O3 -DNDEBUG # default optimization on; override on cli
+### ADS: use AM_CXXFLAGS if these are needed
+## AM_CXXFLAGS = -Wall -Wextra -Wpedantic -Wno-unknown-attributes
 
 TESTS = test/falco.test
 TEST_EXTENSIONS = .test

configure.ac

@@ -24,6 +24,13 @@ AM_INIT_AUTOMAKE([subdir-objects foreign])
 AC_CONFIG_MACRO_DIR([m4])
 AC_LANG(C++)
 AC_PROG_CXX
+
+# Set CXXFLAGS only if the user hasn't set them
+AS_IF([test "x$CXXFLAGS_set" != "xset"], [
+  CXXFLAGS="-O3 -DNDEBUG"
+])
+AC_MSG_NOTICE([CXXFLAGS is $CXXFLAGS])
+
 AX_CXX_COMPILE_STDCXX_17([noext], [mandatory])
 AC_OPENMP([C++]) dnl make sure we have openmp for multi-core in falco