remove --disable-cxx flag

it was getting too hard to support :( automake now generates libtool
lines before configure runs, so it can't know we don't want a C++ link

see https://github.com/jcupitt/libvips/issues/231

ChangeLog

@@ -2,6 +2,7 @@
 - bump version for back-compat ABI change
 - added vips_image_memory(), an alias for vips_image_new_memory()
 - improvements to configure for python
+- remove --disable-cxx configure flag
 
 30/12/14 started 7.42.2
 - C++ required output params were broken, thanks Lovell

Makefile.am

@@ -1,20 +1,9 @@
 
-# turn off C++ APIs if C++ is disabled
+# turn on Python if we can 
-if ENABLE_CXX
-C_COMPILE_DIR = libvipsCC cplusplus
-C_DIST_DIR =
-C_PKGCONFIG = vipsCC.pc vips-cpp.pc
-
-# turn on Python if we can (requires C++)
 if HAVE_PYTHON
 P_COMPILE_DIR = swig
 P_DIST_DIR =
-endif
-
 else
-C_COMPILE_DIR =
-C_DIST_DIR = libvipsCC cplusplus
-C_PKGCONFIG =
 P_COMPILE_DIR =
 P_DIST_DIR = swig
 endif
@@ -39,12 +28,13 @@ endif
 
 SUBDIRS = \
 	libvips \
+	libvipsCC \
+	cplusplus \
 	tools \
 	po \
 	man \
 	doc \
 	test \
-	$(C_COMPILE_DIR) \
 	$(P_COMPILE_DIR) \
 	$(P8_COMPILE_DIR) \
 	$(D_BUILD_DIR) 
@@ -60,13 +50,12 @@ EXTRA_DIST = \
 	acinclude.m4 \
 	depcomp \
 	README.md \
-	$(C_DIST_DIR) \
 	$(P_DIST_DIR) \
 	$(P8_DIST_DIR) \
 	$(D_DIST_DIR)
 
 pkgconfigdir = $(libdir)/pkgconfig
-pkgconfig_DATA = vips.pc $(C_PKGCONFIG)
+pkgconfig_DATA = vips.pc vipsCC.pc vips-cpp.pc
 
 if ENABLE_DOCS
 install-exec-hook:

TODO

@@ -1,3 +1,4 @@
+
 - use vips_resize() in vipsthumbnail?
 
   should the sharpening filter be selectable?

configure.ac

@@ -272,47 +272,6 @@ AC_PROG_INSTALL
 AC_PROG_LN_S
 AM_WITH_DMALLOC
 
-# vips_PROG_CXX_WORKS
-# Check whether the C++ compiler works.
-AC_DEFUN([vips_PROG_CXX_WORKS],
-  [AC_REQUIRE([AC_PROG_CXX])dnl
-   AC_CACHE_CHECK([whether the C++ compiler works],
-   [vips_cv_prog_cxx_works],
-   [AC_LANG_PUSH([C++])
-    AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
-                   [vips_cv_prog_cxx_works=yes],
-                   [vips_cv_prog_cxx_works=no])
-    AC_LANG_POP([C++])])
-])
-
-# option to build without C++
-# handy for some embedded applications
-# also, including C++ source causes link problems on some
-# platforms, so have an option to disable it
-AC_ARG_ENABLE(cxx, 
-  AS_HELP_STRING([--enable-cxx], [build C++ components (default: test)]))
-
-if test x"$enable_cxx" != x"no"; then
-  vips_PROG_CXX_WORKS
-  if test x"$vips_cv_prog_cxx_works" = x"yes"; then 
-    AC_DEFINE(ENABLE_CXX,1,[build C++ components])
-    AM_CONDITIONAL(ENABLE_CXX, true)
-    # need -lstdc++ for (eg.) the C++ format loaders
-    # this gets added to vips.pc to help mingw and friends link programs
-    # using libvips
-    if test x"$vips_needs_stdcpp" != x"no"; then
-      VIPS_CXX_LIBS="-lstdc++"
-    fi
-    enable_cxx=yes
-  fi
-fi
-
-if test x"$enable_cxx" != x"yes"; then
-  AM_CONDITIONAL(ENABLE_CXX, false)
-  VIPS_CXX_LIBS=""
-  enable_cxx=no
-fi
-
 # we need a fully expanded version of $libdir
 # without this we get something like
 #    define VIPS_LIBDIR ${exec_prefix}/lib
@@ -812,7 +771,7 @@ else
   AM_CONDITIONAL(HAVE_PYTHON, false)
 fi
 
-# Gather all up for VIPS_CFLAGS, VIPS_INCLUDES, VIPS_LIBS and VIPS_CXX_LIBS
+# Gather all up for VIPS_CFLAGS, VIPS_INCLUDES, VIPS_LIBS 
 # sort includes to get longer, more specific dirs first
 # helps, for example, selecting graphicsmagick over imagemagick
 VIPS_CFLAGS=`for i in $VIPS_CFLAGS $GTHREAD_CFLAGS $REQUIRED_CFLAGS $PANGOFT2_CFLAGS $GSF_CFLAGS $FFTW_CFLAGS $MAGICK_CFLAGS $PNG_CFLAGS $EXIF_CFLAGS $MATIO_CFLAGS $CFITSIO_CFLAGS $LIBWEBP_CFLAGS $OPENEXR_CFLAGS $OPENSLIDE_CFLAGS $ORC_CFLAGS $TIFF_CFLAGS $LCMS_CFLAGS 
@@ -829,7 +788,6 @@ AC_SUBST(VIPS_LIBDIR)
 AC_SUBST(VIPS_CFLAGS)
 AC_SUBST(VIPS_INCLUDES)
 AC_SUBST(VIPS_LIBS)
-AC_SUBST(VIPS_CXX_LIBS)
 AC_SUBST(PACKAGES_USED)
 AC_SUBST(EXTRA_LIBS_USED)
 
@@ -893,7 +851,6 @@ native OS X:				$vips_os_darwin
 open files in binary mode: 		$vips_binary_open
 enable debug:				$enable_debug
 build deprecated components:		$enable_deprecated
-build C++ components:			$enable_cxx
 build docs with gtkdoc:			$enable_gtk_doc
 install docs:				$enable_docs
 gobject introspection: 			$found_introspection

libvips/Makefile.am

@@ -33,13 +33,8 @@ lib_LTLIBRARIES = libvips.la
 # empty means default to C linking
 libvips_la_SOURCES = 
 
-# if we have C++ components enabled, make sure we link the top-level with c++
+# make sure we link the top-level with c++
-#
-# sadly the if/endif isn't enough to stop automake detecting a c++ link even
-# when c++ is disabled ... comment out this line if you have linking problems
-if ENABLE_CXX
 nodist_EXTRA_libvips_la_SOURCES = resample/dummy2.cc
-endif
 
 # DLLs need dependant libs there too ... put @VIPS_LIBS@ at the end
 libvips_la_LIBADD = \
@@ -60,10 +55,6 @@ libvips_la_LIBADD = \
 	video/libvideo.la \
 	@VIPS_LIBS@
 
-if ENABLE_CXX
-libvips_la_LIBADD += @VIPS_CXX_LIBS@
-endif
-
 libvips_la_LDFLAGS = \
 	-no-undefined \
 	-version-info @LIBRARY_CURRENT@:@LIBRARY_REVISION@:@LIBRARY_AGE@ 
@@ -89,9 +80,6 @@ AM_LDFLAGS = \
 	     @INTROSPECTION_LIBS@ \
 	     @LDFLAGS@ 
 LDADD = @INTROSPECTION_LIBS@ @VIPS_CFLAGS@ libvips.la @VIPS_LIBS@ 
-if ENABLE_CXX
-LDADD += @VIPS_CXX_LIBS@
-endif
 
 noinst_PROGRAMS = \
 	introspect

libvips/resample/Makefile.am

@@ -1,9 +1,3 @@
-# only build the C++ stuff if ENABLE_CXX
-# you'd think we could just define a couple of variables, but that seems to
-# confuse libtool and make it link the library with g++
-# instead, have two completely different paths
-if ENABLE_CXX
-
 libresample_la_SOURCES = \
 	affine.c \
 	quadratic.c \
@@ -23,29 +17,6 @@ libresample_la_SOURCES = \
 EXTRA_DIST = \
 	dummy2.cc 
 
-else
-
-libresample_la_SOURCES = \
-	resample.c \
-	similarity.c \
-	presample.h \
-	resize.c \
-	shrink.c \
-	affine.c \
-	interpolate.c \
-	quadratic.c \
-	transform.c 
-
-EXTRA_DIST = \
-	dummy2.cc \
-	bicubic.cpp \
-	lbb.cpp \
-	nohalo.cpp \
-	vsqbs.cpp \
-	templates.h 
-
-endif
-
 noinst_LTLIBRARIES = libresample.la
 
 AM_CPPFLAGS = -I${top_srcdir}/libvips/include @VIPS_CFLAGS@ @VIPS_INCLUDES@ 

tools/Makefile.am

@@ -12,9 +12,6 @@ vipsthumbnail_SOURCES = vipsthumbnail.c
 AM_CPPFLAGS = -I${top_srcdir}/libvips/include @VIPS_CFLAGS@ @VIPS_INCLUDES@
 AM_LDFLAGS = @LDFLAGS@ 
 LDADD = @VIPS_CFLAGS@ ${top_builddir}/libvips/libvips.la @VIPS_LIBS@
-if ENABLE_CXX
-LDADD += @VIPS_CXX_LIBS@
-endif
 
 bin_SCRIPTS = \
 	light_correct \