arthurdejong · salahcoronya · Jul 7, 2024
diff --git a/common/Makefile.am b/common/Makefile.am
@@ -20,7 +20,7 @@
 noinst_LIBRARIES = libtio.a libprot.a libdict.a libexpr.a
 
 AM_CPPFLAGS=-I$(top_srcdir)
-AM_CFLAGS = $(PIC_CFLAGS)
+AM_CFLAGS = $(PIC_CFLAGS) $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 libtio_a_SOURCES = tio.c tio.h
 

diff --git a/compat/Makefile.am b/compat/Makefile.am
@@ -20,7 +20,7 @@
 noinst_LIBRARIES = libcompat.a
 
 AM_CPPFLAGS=-I$(top_srcdir)
-AM_CFLAGS = $(PIC_CFLAGS)
+AM_CFLAGS = $(PIC_CFLAGS) $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 EXTRA_DIST = getopt_long.c getopt_long.h \
              ether.c ether.h \

diff --git a/configure.ac b/configure.ac
@@ -101,39 +101,25 @@ then
 fi
 
 # check for debugging options
+DEBUG_CFLAGS=""
 AC_ARG_ENABLE(debug,
               AS_HELP_STRING([--enable-debug],
                              [enable extensive debugging and logging]),
-              [if test "x$enableval" != "xno" ; then CFLAGS="-g -DDEBUG $CFLAGS" ; fi])
+              [AS_IF([test "x$enableval" != "xno"],
+		    [AX_APPEND_COMPILE_FLAGS([-g -DDEBUG],[DEBUG_CFLAGS])]
+              )])
+AC_SUBST([DEBUG_CFLAGS])
 
 # check for extra compiler warnings
-DESIRED_CFLAGS=""
+EXTRA_CFLAGS=""
 AC_ARG_ENABLE(warnings,
               AS_HELP_STRING([--enable-warnings],
                              [enable extra compiler warnings (gcc)]),
-              [if test "x$enableval" != "no"
-               then
-                 CFLAGS="$CFLAGS -pedantic -Wall -Wshadow -Wpointer-arith -Wcast-align -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Waggregate-return -Wmissing-declarations -Wunused -Wformat=2 -Wswitch-default -Wswitch-enum -Wfloat-equal -Wbad-function-cast -Wredundant-decls"
-                 DESIRED_CFLAGS="$DESIRED_CFLAGS -Wextra -Wdeclaration-after-statement -Werror-implicit-function-declaration -Werror=implicit"
-               fi])
-test_gcc_flag() {
-  AC_LANG_CONFTEST([AC_LANG_PROGRAM()])
-  $CC -c conftest.c $CFLAGS $@ > /dev/null 2> /dev/null
-  ret=$?
-  rm -f conftest.o
-  return $ret
-}
-for flag in $DESIRED_CFLAGS
-do
-  AC_MSG_CHECKING([whether $CC accepts $flag])
-  if test_gcc_flag $flag
-  then
-    CFLAGS="$CFLAGS $flag"
-    AC_MSG_RESULT([yes])
-  else
-    AC_MSG_RESULT([no])
-  fi
-done
+              [AS_IF([test "x$enableval" != "xno"],[
+                 AX_APPEND_COMPILE_FLAGS([-pedantic -Wall -Wshadow -Wpointer-arith -Wcast-align -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Waggregate-return -Wmissing-declarations -Wunused -Wformat=2 -Wswitch-default -Wswitch-enum -Wfloat-equal -Wbad-function-cast -Wredundant-decls],[EXTRA_CFLAGS],[-Werror])
+                 AX_APPEND_COMPILE_FLAGS([-Wextra -Wdeclaration-after-statement -Werror-implicit-function-declaration -Werror=implicit],[EXTRA_CFLAGS],[-Werror])
+               ])])
+AC_SUBST([EXTRA_CFLAGS])
 
 # check for Position Independent Code compiler option
 PIC_CFLAGS=""

diff --git a/m4/ax_append_compile_flags.m4 b/m4/ax_append_compile_flags.m4
@@ -0,0 +1,46 @@
+# ============================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_append_compile_flags.html
+# ============================================================================
+#
+# SYNOPSIS
+#
+#   AX_APPEND_COMPILE_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS], [INPUT])
+#
+# DESCRIPTION
+#
+#   For every FLAG1, FLAG2 it is checked whether the compiler works with the
+#   flag.  If it does, the flag is added FLAGS-VARIABLE
+#
+#   If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
+#   CFLAGS) is used.  During the check the flag is always added to the
+#   current language's flags.
+#
+#   If EXTRA-FLAGS is defined, it is added to the current language's default
+#   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
+#   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
+#   force the compiler to issue an error when a bad flag is given.
+#
+#   INPUT gives an alternative input source to AC_COMPILE_IFELSE.
+#
+#   NOTE: This macro depends on the AX_APPEND_FLAG and
+#   AX_CHECK_COMPILE_FLAG. Please keep this macro in sync with
+#   AX_APPEND_LINK_FLAGS.
+#
+# LICENSE
+#
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 7
+
+AC_DEFUN([AX_APPEND_COMPILE_FLAGS],
+[AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
+AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+for flag in $1; do
+  AX_CHECK_COMPILE_FLAG([$flag], [AX_APPEND_FLAG([$flag], [$2])], [], [$3], [$4])
+done
+])dnl AX_APPEND_COMPILE_FLAGS
diff --git a/m4/ax_append_flag.m4 b/m4/ax_append_flag.m4
@@ -0,0 +1,50 @@
+# ===========================================================================
+#      https://www.gnu.org/software/autoconf-archive/ax_append_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_APPEND_FLAG(FLAG, [FLAGS-VARIABLE])
+#
+# DESCRIPTION
+#
+#   FLAG is appended to the FLAGS-VARIABLE shell variable, with a space
+#   added in between.
+#
+#   If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
+#   CFLAGS) is used.  FLAGS-VARIABLE is not changed if it already contains
+#   FLAG.  If FLAGS-VARIABLE is unset in the shell, it is set to exactly
+#   FLAG.
+#
+#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 8
+
+AC_DEFUN([AX_APPEND_FLAG],
+[dnl
+AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_SET_IF
+AS_VAR_PUSHDEF([FLAGS], [m4_default($2,_AC_LANG_PREFIX[FLAGS])])
+AS_VAR_SET_IF(FLAGS,[
+  AS_CASE([" AS_VAR_GET(FLAGS) "],
+    [*" $1 "*], [AC_RUN_LOG([: FLAGS already contains $1])],
+    [
+     AS_VAR_APPEND(FLAGS,[" $1"])
+     AC_RUN_LOG([: FLAGS="$FLAGS"])
+    ])
+  ],
+  [
+  AS_VAR_SET(FLAGS,[$1])
+  AC_RUN_LOG([: FLAGS="$FLAGS"])
+  ])
+AS_VAR_POPDEF([FLAGS])dnl
+])dnl AX_APPEND_FLAG
diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4
@@ -0,0 +1,53 @@
+# ===========================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
+#
+# DESCRIPTION
+#
+#   Check whether the given FLAG works with the current language's compiler
+#   or gives an error.  (Warnings, however, are ignored)
+#
+#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
+#   success/failure.
+#
+#   If EXTRA-FLAGS is defined, it is added to the current language's default
+#   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
+#   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
+#   force the compiler to issue an error when a bad flag is given.
+#
+#   INPUT gives an alternative input source to AC_COMPILE_IFELSE.
+#
+#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+#   macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 6
+
+AC_DEFUN([AX_CHECK_COMPILE_FLAG],
+[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
+AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
+  ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
+  _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
+  AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
+    [AS_VAR_SET(CACHEVAR,[yes])],
+    [AS_VAR_SET(CACHEVAR,[no])])
+  _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
+AS_VAR_IF(CACHEVAR,yes,
+  [m4_default([$2], :)],
+  [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_COMPILE_FLAGS
diff --git a/m4/ax_require_defined.m4 b/m4/ax_require_defined.m4
@@ -0,0 +1,37 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_require_defined.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_REQUIRE_DEFINED(MACRO)
+#
+# DESCRIPTION
+#
+#   AX_REQUIRE_DEFINED is a simple helper for making sure other macros have
+#   been defined and thus are available for use.  This avoids random issues
+#   where a macro isn't expanded.  Instead the configure script emits a
+#   non-fatal:
+#
+#     ./configure: line 1673: AX_CFLAGS_WARN_ALL: command not found
+#
+#   It's like AC_REQUIRE except it doesn't expand the required macro.
+#
+#   Here's an example:
+#
+#     AX_REQUIRE_DEFINED([AX_CHECK_LINK_FLAG])
+#
+# LICENSE
+#
+#   Copyright (c) 2014 Mike Frysinger <vapier@gentoo.org>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 2
+
+AC_DEFUN([AX_REQUIRE_DEFINED], [dnl
+  m4_ifndef([$1], [m4_fatal([macro ]$1[ is not defined; is a m4 file missing?])])
+])dnl AX_REQUIRE_DEFINED
diff --git a/nslcd/Makefile.am b/nslcd/Makefile.am
@@ -21,7 +21,7 @@
 sbin_PROGRAMS = nslcd
 
 AM_CPPFLAGS=-I$(top_srcdir)
-AM_CFLAGS = $(PTHREAD_CFLAGS)
+AM_CFLAGS = $(PTHREAD_CFLAGS) $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 nslcd_SOURCES = nslcd.c ../nslcd.h ../common/nslcd-prot.h \
                 ../compat/attrs.h \

diff --git a/nss/Makefile.am b/nss/Makefile.am
@@ -23,7 +23,7 @@
 noinst_PROGRAMS = nss_ldap.so
 
 AM_CPPFLAGS=-I$(top_srcdir)
-AM_CFLAGS = $(PIC_CFLAGS)
+AM_CFLAGS = $(PIC_CFLAGS) $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 nss_ldap_so_SOURCES = common.c common.h prototypes.h solnss.h \
                       ../nslcd.h ../common/nslcd-prot.h \

diff --git a/pam/Makefile.am b/pam/Makefile.am
@@ -21,7 +21,7 @@
 noinst_PROGRAMS = pam_ldap.so
 
 AM_CPPFLAGS=-I$(top_srcdir)
-AM_CFLAGS = $(PIC_CFLAGS)
+AM_CFLAGS = $(PIC_CFLAGS) $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 pam_ldap_so_SOURCES = ../nslcd.h ../common/nslcd-prot.h \
                       ../compat/attrs.h pam.c common.h

diff --git a/tests/Makefile.am b/tests/Makefile.am
@@ -58,7 +58,7 @@ clean-local:
 	-rm -rf *.pyc *.pyo __pycache__ flake8-venv
 
 AM_CPPFLAGS = -I$(top_srcdir)
-AM_CFLAGS = $(PTHREAD_CFLAGS) -g
+AM_CFLAGS = $(PTHREAD_CFLAGS) -g $(DEBUG_CFLAGS) $(EXTRA_CFLAGS)
 
 test_dict_SOURCES = test_dict.c ../common/dict.h
 test_dict_LDADD = ../common/libdict.a