From d6850eb4ad81e1dce6fa8745e0b7e566cf41fb32 Mon Sep 17 00:00:00 2001
From: Brad House <brad@brad-house.com>
Date: Thu, 18 Jan 2024 07:41:46 -0500
Subject: [PATCH] Autotools allow make to override CFLAGS/CPPFLAGS/CXXFLAGS
(#695)
The previous build system allowed overwriting of CFLAGS/CPPFLAGS/CXXFLAGS on the make command line. Switch to using AM_CFLAGS/AM_CPPFLAGS/AM_CXXFLAGS when we set our own flags for building which ensures they are kept even when a user tries to override.
Fixes Bug: #694
Fix By: Brad House (@bradh352)
---
configure.ac | 66 +++++++++++++++++++++++--------------------
src/lib/Makefile.am | 8 +++---
src/tools/Makefile.am | 8 +++---
test/Makefile.am | 22 ++++++++-------
4 files changed, 56 insertions(+), 48 deletions(-)
diff --git a/configure.ac b/configure.ac
index 1d641c6f..65ced501 100644
--- a/configure.ac
+++ b/configure.ac
@@ -42,8 +42,7 @@ AC_CONFIG_MACRO_DIR([m4])
AC_USE_SYSTEM_EXTENSIONS
AX_CXX_COMPILE_STDCXX_14([noext],[optional])
AM_INIT_AUTOMAKE([foreign subdir-objects 1.9.6])
-AC_ENABLE_SHARED
-LT_INIT([win32-dll,shared,pic,disable-fast-install,aix-soname=svr4])
+LT_INIT([win32-dll,pic,disable-fast-install,aix-soname=svr4])
AC_LANG([C])
AC_PROG_CC
AM_PROG_CC_C_O
@@ -52,6 +51,31 @@ AC_PROG_INSTALL
AC_CANONICAL_HOST
AX_COMPILER_VENDOR
+AC_MSG_CHECKING([whether this is native windows])
+ac_cv_native_windows=no
+ac_cv_windows=no
+case $host_os in
+ mingw*)
+ ac_cv_native_windows=yes
+ ac_cv_windows=yes
+ ;;
+ cygwin*)
+ ac_cv_windows=yes
+ ;;
+esac
+if test "$ax_cv_c_compiler_vendor" = "microsoft" ; then
+ ac_cv_native_windows=yes
+ ac_cv_windows=yes
+fi
+AC_MSG_RESULT($ac_cv_native_windows)
+
+
+AC_ENABLE_SHARED
+
+dnl Disable static builds by default on Windows unless overwritten since Windows
+dnl can't simultaneously build shared and static with autotools.
+AS_IF([test "x$ac_cv_windows" = "xyes"], [AC_DISABLE_STATIC], [AC_ENABLE_STATIC])
+
AC_ARG_ENABLE(warnings,
AS_HELP_STRING([--disable-warnings],[Disable strict compiler warnings]),
[ enable_warnings=${enableval} ],
@@ -162,39 +186,20 @@ esac
AM_CONDITIONAL([CARES_USE_NO_UNDEFINED], [test "$cares_use_no_undefined" = 'yes'])
-AC_MSG_CHECKING([whether this is native windows])
-ac_cv_native_windows=no
-ac_cv_windows=no
-case $host_os in
- mingw*)
- ac_cv_native_windows=yes
- ac_cv_windows=yes
- ;;
- cygwin*)
- ac_cv_windows=yes
- ;;
-esac
-if test "$ax_cv_c_compiler_vendor" = "microsoft" ; then
- ac_cv_native_windows=yes
- ac_cv_windows=yes
-fi
if test "$ac_cv_native_windows" = "yes" ; then
- CPPFLAGS="$CPPFLAGS -D_WIN32_WINNT=0x0602 -DWIN32_LEAN_AND_MEAN"
+ AM_CPPFLAGS="$AM_CPPFLAGS -D_WIN32_WINNT=0x0602 -DWIN32_LEAN_AND_MEAN"
fi
-AC_MSG_RESULT($ac_cv_native_windows)
-dnl Disable static builds by default on Windows unless overwritten since Windows
-dnl can't simultaneously build shared and static with autotools.
-if test "x$ac_cv_windows" = "xyes" ; then
- AC_DISABLE_STATIC
+dnl Windows can only build shared or static, not both at the same time
+if test "$ac_cv_native_windows" = "yes" -a "x$enable_shared" = "xyes" -a "x$enable_static" = "xyes" ; then
+ AC_MSG_ERROR([Windows cannot build both static and shared simultaneously, specify --disable-shared or --disable-static])
fi
-
dnl Only windows requires CARES_STATICLIB definition
if test "x$enable_shared" = "xno" -a "x$enable_static" = "xyes" ; then
AC_MSG_CHECKING([whether we need CARES_STATICLIB definition])
if test "$ac_cv_native_windows" = "yes" ; then
- AX_APPEND_FLAG([-DCARES_STATICLIB], [CPPFLAGS])
+ AX_APPEND_FLAG([-DCARES_STATICLIB], [AM_CPPFLAGS])
AC_MSG_RESULT([yes])
else
AC_MSG_RESULT([no])
@@ -274,11 +279,11 @@ if test "$enable_warnings" = "yes"; then
-Werror=implicit-int \
-Werror=implicit-function-declaration \
-Werror=partial-availability \
- ], [CFLAGS], [-Werror])
+ ], [AM_CFLAGS], [-Werror])
fi
if test "$ax_cv_c_compiler_vendor" = "intel"; then
- CFLAGS="$CFLAGS -shared-intel"
+ AX_APPEND_COMPILE_FLAGS([-shared-intel], [AM_CFLAGS])
fi
if test "$ac_cv_native_windows" = "yes" ; then
@@ -818,7 +823,7 @@ if test "${CARES_THREADS}" = "yes" -a "x${ac_cv_native_windows}" != "xyes" ; the
if test "${CARES_THREADS}" = "yes" ; then
AC_CHECK_HEADERS([pthread.h pthread_np.h])
LIBS="$PTHREAD_LIBS $LIBS"
- CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+ AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS"
CC="$PTHREAD_CC"
CXX="$PTHREAD_CXX"
fi
@@ -876,9 +881,10 @@ fi
AC_MSG_CHECKING([whether to build tests])
AC_MSG_RESULT([$build_tests])
-
AM_CONDITIONAL(BUILD_TESTS, test "x$build_tests" = "xyes")
+AC_SUBST(AM_CFLAGS)
+AC_SUBST(AM_CPPFLAGS)
AC_SUBST(BUILD_SUBDIRS)
AC_CONFIG_FILES([Makefile \
diff --git a/src/lib/Makefile.am b/src/lib/Makefile.am
index 39f28578..44e04bd3 100644
--- a/src/lib/Makefile.am
+++ b/src/lib/Makefile.am
@@ -8,10 +8,10 @@ ACLOCAL_AMFLAGS = -I m4 --install
# being currently built and tested are searched before the library which
# might possibly already be installed in the system.
-AM_CPPFLAGS = -I$(top_builddir)/include \
- -I$(top_builddir)/src/lib \
- -I$(top_srcdir)/include \
- -I$(top_srcdir)/src/lib
+AM_CPPFLAGS += -I$(top_builddir)/include \
+ -I$(top_builddir)/src/lib \
+ -I$(top_srcdir)/include \
+ -I$(top_srcdir)/src/lib
lib_LTLIBRARIES = libcares.la
diff --git a/src/tools/Makefile.am b/src/tools/Makefile.am
index 0545c064..729658d7 100644
--- a/src/tools/Makefile.am
+++ b/src/tools/Makefile.am
@@ -12,10 +12,10 @@ noinst_PROGRAMS =$(PROGS)
# being currently built and tested are searched before the library which
# might possibly already be installed in the system.
-AM_CPPFLAGS = -I$(top_builddir)/include \
- -I$(top_builddir)/src/lib \
- -I$(top_srcdir)/include \
- -I$(top_srcdir)/src/lib
+AM_CPPFLAGS += -I$(top_builddir)/include \
+ -I$(top_builddir)/src/lib \
+ -I$(top_srcdir)/include \
+ -I$(top_srcdir)/src/lib
include Makefile.inc
diff --git a/test/Makefile.am b/test/Makefile.am
index a84906dc..62d421aa 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -2,15 +2,17 @@
# SPDX-License-Identifier: MIT
AUTOMAKE_OPTIONS = foreign subdir-objects nostdinc 1.9.6
-AM_CPPFLAGS = -I$(top_builddir)/include \
- -I$(top_builddir)/src/lib \
- -I$(top_srcdir)/include \
- -I$(top_srcdir)/src/lib \
- -I$(top_srcdir)/test \
- -I$(top_builddir)/test \
- -I$(top_builddir)
-AM_CXXFLAGS = $(PTHREAD_CFLAGS)
-AM_CFLAGS = $(PTHREAD_CFLAGS)
+AM_CPPFLAGS += -I$(top_builddir)/include \
+ -I$(top_builddir)/src/lib \
+ -I$(top_srcdir)/include \
+ -I$(top_srcdir)/src/lib \
+ -I$(top_srcdir)/test \
+ -I$(top_builddir)/test \
+ -I$(top_builddir)
+
+AM_CXXFLAGS :=
+AM_CXXFLAGS += $(PTHREAD_CFLAGS)
+AM_CFLAGS += $(PTHREAD_CFLAGS)
# Makefile.inc provides the various *SOURCES and *HEADERS defines
include Makefile.inc
@@ -22,7 +24,7 @@ EXTRA_DIST = fuzzcheck.sh CMakeLists.txt Makefile.m32 Makefile.msvc README.md $(
arestest_SOURCES = $(TESTSOURCES) $(TESTHEADERS)
# Not interested in coverage of test code, but linking the test binary needs the coverage option
-arestest_CXXFLAGS = $(GMOCK_CFLAGS)
+arestest_CXXFLAGS = $(AM_CXXFLAGS) $(GMOCK_CFLAGS)
arestest_LDADD = $(GMOCK_LIBS) $(top_builddir)/src/lib/libcares.la $(PTHREAD_LIBS) $(CODE_COVERAGE_LIBS)
aresfuzz_SOURCES = $(FUZZSOURCES)