changeset 31153:8f67b53ac9ff

configure.ac: clean up ordering of macros, comments. * configure.ac: Use consistent wording for section headings (/^###/). Re-order macros to put more important tests first and group related macros.
author Rik <rik@octave.org>
date Tue, 26 Jul 2022 17:20:13 -0700
parents 839c0fb5d63c
children 929c05cf2afa
files configure.ac
diffstat 1 files changed, 97 insertions(+), 96 deletions(-) [+]
line wrap: on
line diff
--- a/configure.ac	Tue Jul 26 17:05:33 2022 -0700
+++ b/configure.ac	Tue Jul 26 17:20:13 2022 -0700
@@ -135,7 +135,7 @@
   '${libdir}/octave/${version}/oct/${canonical_host_type}')
 
 ## Directories that Octave should search for object files that will be
-## dynamically loaded and that are specific to this site (i.e. customizations),
+## dynamically loaded and that are specific to this site (i.e., customizations),
 ## before consulting ${octfiledir}.  This should be a colon-separated list of
 ## directories.
 OCTAVE_SET_DEFAULT([localoctfiledir],
@@ -156,7 +156,7 @@
 OCTAVE_SET_DEFAULT([fcnfiledir], '${datadir}/octave/${version}/m')
 
 ## Directories that Octave should search for function files specific to this
-## site (i.e. customizations), before consulting ${fcnfiledir}.
+## site (i.e., customizations), before consulting ${fcnfiledir}.
 ## This should be a colon-separated list of directories.
 OCTAVE_SET_DEFAULT([localfcnfiledir], '${datadir}/octave/site/m')
 
@@ -252,7 +252,7 @@
 AM_CONDITIONAL([AMCOND_HAVE_ICON_TOOLS],
   [test -n "$ICOTOOL" && test -n "$RSVG_CONVERT"])
 
-### Path separator.
+### Determine path separator.
 
 sepchar=':'
 AC_ARG_WITH([sepchar],
@@ -279,9 +279,9 @@
   [Define this to be the path separator for your system, as a string.])
 
 ### Define the path to the shell on the host system.
-### Most systems will ensure /bin/sh is the default shell so this can be safely
-### ignored by almost everyone.  However, when building for Android, for
-### example, this will need to be set.
+dnl Most systems will ensure /bin/sh is the default shell so this can be safely
+dnl ignored by almost everyone.  However, there are exceptions, such as
+dnl Android, where this will need to be set.
 SHELL_PATH=/bin/sh
 AC_ARG_WITH([shell],
   [AS_HELP_STRING([--with-shell=SHELL],
@@ -299,34 +299,6 @@
 AC_DEFINE_UNQUOTED([SHELL_PATH], ["$SHELL_PATH"],
   [Define this to be the path to the shell command interpreter.])
 
-### Use the system-wide installation of GNU FreeFont if the user requests it.
-### By default, Octave includes its own copy of the FreeSans font, which it
-### installs in its own directory for use as a fallback default font.  If this
-### configuration option is used, then do not install our own copy of the fonts
-### and assume they can be found in the provided system directory.
-SYSTEM_FREEFONT_DIR=
-AC_ARG_WITH([system-freefont],
-  [AS_HELP_STRING([--with-system-freefont=DIR],
-    [use FreeSans fonts in DIR (default: install and use internal copy)])])
-case $with_system_freefont in
-  no | "")
-    SYSTEM_FREEFONT_DIR=
-    ;;
-  yes)
-    AC_MSG_ERROR([directory argument required for --with-system-freefont])
-    ;;
-  *)
-    SYSTEM_FREEFONT_DIR=$with_system_freefont
-    ;;
-esac
-if test -n "$SYSTEM_FREEFONT_DIR"; then
-  AC_MSG_NOTICE([configuring Octave to use system fonts in $SYSTEM_FREEFONT_DIR])
-  AC_DEFINE_UNQUOTED([SYSTEM_FREEFONT_DIR], ["$SYSTEM_FREEFONT_DIR"],
-    [Define this to be the system directory containing the GNU FreeFont fonts.])
-fi
-AM_CONDITIONAL([AMCOND_INSTALL_INTERNAL_FONT_FILES],
-  [test -z "$SYSTEM_FREEFONT_DIR"])
-
 ### Determine which C++ compiler to use (we expect to find g++).
 
 AC_PROG_CXX
@@ -335,14 +307,14 @@
 ENABLE_STD_PMR_POLYMORPHIC_ALLOCATOR=no
 AC_ARG_ENABLE(std-pmr-polymorphic-allocator,
   [AS_HELP_STRING([--enable-std-pmr-polymorphic-allocator],
-    [build libraries requiring std::pmr::polymorphic_allocator if possible. This allows more efficient transfer of arrays at the .mex file interface. That also means that all libraries including Octave headers (e.g., .oct files) must be able to compile with that C++17 feature.])],
+    [build libraries requiring std::pmr::polymorphic_allocator if possible.  This allows more efficient transfer of arrays at the .mex file interface.  That also means that all libraries including Octave headers (e.g., .oct files) must be able to compile with that C++17 feature.])],
   [case $enableval in
      yes) ENABLE_STD_PMR_POLYMORPHIC_ALLOCATOR=yes ;;
      no) ENABLE_STD_PMR_POLYMORPHIC_ALLOCATOR=no ;;
      *) AC_MSG_ERROR([bad value $enableval for --enable-std-pmr-polymorphic-allocator]) ;;
    esac])
 
-### Check compiler capabilities.
+### Determine compiler capabilities.
 
 if test $ENABLE_STD_PMR_POLYMORPHIC_ALLOCATOR = yes; then
   ## Test for flags to fully support C++17.
@@ -487,7 +459,7 @@
 dnl in case -lm is needed to compile Fortran programs.
 AC_CHECK_LIB(m, sin)
 
-### Determine the Fortran compiler and how to invoke it
+### Determine the Fortran compiler and how to invoke it.
 
 ## Prefer gfortran, but the user's F77 environment variable will override.
 AC_PROG_F77([gfortran])
@@ -511,10 +483,10 @@
 AC_F77_DUMMY_MAIN
 AC_F77_WRAPPERS
 
-### Must appear after checks for Fortran compiler.
+## Must appear after checks for Fortran compiler.
 OCTAVE_CHECK_FORTRAN_SYMBOL_AND_CALLING_CONVENTIONS
 
-### Must appear after checks for compilers.
+## Must appear after checks for all compilers.
 OCTAVE_DEFINE_MKOCTFILE_DYNAMIC_LINK_OPTIONS
 
 ### Use a 64-bit integer type for array dimensions and indexing, if possible.
@@ -568,7 +540,7 @@
 AC_DEFINE_UNQUOTED(OCTAVE_IDX_TYPE, [$OCTAVE_IDX_TYPE],
   [Define to the type of octave_idx_type (64 or 32 bit signed integer).])
 
-### Check for pthread library
+### Check for pthread library.
 
 AX_PTHREAD
 dnl Include pthread libs and flags early in case other config tests need them.
@@ -586,7 +558,6 @@
 AM_CONDITIONAL([OCTAVE_CHECK_BROKEN_PTHREAD_STACKSIZE],
   [test $octave_cv_broken_pthread_stacksize = yes])
 
-
 ### Test whether the compiler supports OpenMP.
 dnl This is enabled by default to allow the option of using OpenMP in
 dnl loadable modules.
@@ -619,7 +590,7 @@
   AC_DEFINE(OCTAVE_ENABLE_OPENMP, 1, [Define to 1 if OpenMP is enabled])
 fi
 
-### Start determination of shared vs. static libraries
+### Start determination of shared vs. static libraries.
 
 ## Use -static if compiling on Alpha OSF/1 1.3 systems.
 case $canonical_host_type in
@@ -670,7 +641,6 @@
   AC_MSG_ERROR([You can't disable building both static AND shared libraries!])
 fi
 
-
 ### More configure argument checking related to linking
 
 case $host_os in
@@ -683,7 +653,7 @@
 esac
 AC_ARG_ENABLE([no-undefined],
   [AS_HELP_STRING([--enable-no-undefined],
-    [pass -no-undefined to libtool when linking Octave and its shared libraries. This is done by default for msdosmsvc, mingw*, AIX, BeOS, or OS/2 hosts.])],
+    [pass -no-undefined to libtool when linking Octave and its shared libraries.  This is done by default for msdosmsvc, mingw*, AIX, BeOS, or OS/2 hosts.])],
   [case $enableval in
      yes) NO_UNDEFINED_LDFLAG="-no-undefined" ;;
      no)  NO_UNDEFINED_LDFLAG="" ;;
@@ -704,7 +674,7 @@
   [link_all_deps=no])
 AM_CONDITIONAL([AMCOND_LINK_ALL_DEPS], [test $link_all_deps = yes])
 
-### Check for BLAS and LAPACK libraries:
+### Check for BLAS and LAPACK libraries.
 
 ## Need to adjust FFLAGS to include correct integer size.
 save_FFLAGS="$FFLAGS"
@@ -863,8 +833,9 @@
 AM_CONDITIONAL([AMCOND_BUILD_EXTERNAL_LIBXERBLA],
   [test -n "$BUILD_EXTERNAL_LIBXERBLA"])
 
-### Dynamic linking is now enabled only if we are building shared
-### libs and some API for dynamic linking has been detected.
+### Set options for dynamic linking if enabled.
+dnl Options set only only if we are building shared libs and some API for
+dnl dynamic linking has been detected.
 
 dnl FIXME: A lot of the following duplicates the functionality of
 dnl code generated by the dlopen option for LT_INIT.
@@ -1383,7 +1354,7 @@
     [Define to 1 to use Bison's push parser interface in the command line REPL.])
 fi
 
-### Configuring building of *experimental* Virtual Machine evaluator
+### Configure compilation of *experimental* Virtual Machine evaluator.
 
 ENABLE_VM_EVALUATOR=yes
 AC_ARG_ENABLE([vm-evaluator],
@@ -1395,7 +1366,16 @@
     [Define to 1 to build experimental Virtual Machine evaluator.])
 fi
 
-### Check for the Qhull library.
+### Check for PCRE regex library.
+
+OCTAVE_CHECK_LIB(pcre, PCRE,
+  [], [pcre.h pcre/pcre.h], [pcre_compile], [], [],
+  [OCTAVE_CHECK_LIB_PCRE_OK([],
+    [AC_MSG_ERROR([PCRE library must be built with UTF support (--enable-utf)])])
+  ],
+  [libpcre], [REQUIRED])
+
+### Check for Qhull library.
 
 QHULL_CPPFLAGS=
 QHULL_LDFLAGS=
@@ -1416,16 +1396,7 @@
 AC_SUBST(QHULL_LDFLAGS)
 AC_SUBST(QHULL_LIBS)
 
-### Check for PCRE regex library.
-
-OCTAVE_CHECK_LIB(pcre, PCRE,
-  [], [pcre.h pcre/pcre.h], [pcre_compile], [], [],
-  [OCTAVE_CHECK_LIB_PCRE_OK([],
-    [AC_MSG_ERROR([PCRE library must be built with UTF support (--enable-utf)])])
-  ],
-  [libpcre], [REQUIRED])
-
-### Check for RapidJSON header only library.
+### Check for RapidJSON header-only library.
 
 check_for_rapidjson=yes
 AC_ARG_ENABLE([rapidjson],
@@ -1530,7 +1501,7 @@
 fi
 
 ### Check for FFTW library.
-### Default to Fortran FFTPACK if it is not available.
+dnl Default to Fortran FFTPACK if it is not available.
 
 ## Check for FFTW header and library.
 OCTAVE_CHECK_LIB(fftw3, FFTW3,
@@ -1565,7 +1536,7 @@
   build_fftw_threads=no
 fi
 
-## Check for the multithreaded FFTW library.
+## Check for multithreaded FFTW library.
 ## Fallback to singlethreaded if not found or disabled.
 if test $build_fftw_threads = yes; then
   OCTAVE_CHECK_FFTW_THREADS(fftw3, fftw_plan_with_nthreads)
@@ -1608,7 +1579,7 @@
 LIBS="$save_LIBS"
 CPPFLAGS="$save_CPPFLAGS"
 
-### Checks for cURL header and library.
+### Check for cURL library existence and functionality.
 
 save_CPPFLAGS="$CPPFLAGS"
 save_LIBS="$LIBS"
@@ -1648,7 +1619,7 @@
     [AC_DEFINE(HAVE_SNDFILE, 1, [Define to 1 if sndfile is available.])],
     [warn_sndfile="sndfile library found, but does not seem to work properly; disabling audio file I/O functions"])])
 
-### Check for PortAudio
+### Check for PortAudio library.
 
 OCTAVE_CHECK_LIB(portaudio, PortAudio,
   [PortAudio library not found.  The audioplayer, audiorecorder, and audiodevinfo functions will be disabled.],
@@ -1656,7 +1627,7 @@
   [], [don't use PortAudio library, disable audio playback and recording],
   [], [portaudio-2.0])
 
-### Check for either of Graphics/ImageMagick++ libraries.
+### Check for either of GraphicsMagick++/ImageMagick++ libraries.
 
 check_magick=yes
 use_magick=no
@@ -1735,7 +1706,7 @@
 AC_SUBST(MAGICK_LDFLAGS)
 AC_SUBST(MAGICK_LIBS)
 
-### Check for X11 libraries
+### Check for X11 libraries.
 
 AC_PATH_X
 if test "$have_x" = yes; then
@@ -1883,7 +1854,7 @@
 AC_SUBST(DEFAULT_TERMINAL_FONT)
 AC_SUBST(DEFAULT_TERMINAL_FONT_SIZE)
 
-### Check for FLTK library
+### Check for FLTK library.
 
 check_fltk=yes
 build_fltk_graphics=no
@@ -1998,7 +1969,7 @@
 AC_SUBST(FLTK_LDFLAGS)
 AC_SUBST(FLTK_LIBS)
 
-### Final determination of whether OpenGL graphics can be built
+### Final determination of whether OpenGL graphics can be built.
 if test $build_qt_graphics = no && test $build_fltk_graphics = no; then
   opengl_graphics=no
 else
@@ -2024,7 +1995,35 @@
   AC_SUBST(GL2PS_LIBS)
 fi
 
-### Check for the qrupdate library
+### Use the system-wide installation of GNU FreeFont if the user requests it.
+dnl By default, Octave includes its own copy of the FreeSans font which it
+dnl installs in its own directory for use as a fallback default font.  If this
+dnl configuration option is used, then do not install our own copy of the fonts
+dnl and assume they can be found in the provided system directory.
+SYSTEM_FREEFONT_DIR=
+AC_ARG_WITH([system-freefont],
+  [AS_HELP_STRING([--with-system-freefont=DIR],
+    [use FreeSans fonts in DIR (default: install and use internal copy)])])
+case $with_system_freefont in
+  no | "")
+    SYSTEM_FREEFONT_DIR=
+    ;;
+  yes)
+    AC_MSG_ERROR([directory argument required for --with-system-freefont])
+    ;;
+  *)
+    SYSTEM_FREEFONT_DIR=$with_system_freefont
+    ;;
+esac
+if test -n "$SYSTEM_FREEFONT_DIR"; then
+  AC_MSG_NOTICE([configuring Octave to use system fonts in $SYSTEM_FREEFONT_DIR])
+  AC_DEFINE_UNQUOTED([SYSTEM_FREEFONT_DIR], ["$SYSTEM_FREEFONT_DIR"],
+    [Define this to be the system directory containing the GNU FreeFont fonts.])
+fi
+AM_CONDITIONAL([AMCOND_INSTALL_INTERNAL_FONT_FILES],
+  [test -z "$SYSTEM_FREEFONT_DIR"])
+
+### Check for qrupdate library.
 
 dnl No need to adjust FFLAGS because only link is attempted.
 dnl Must supply proper LIBS, however.
@@ -2078,11 +2077,11 @@
   SUITESPARSECONFIG_LIBS="$SUITESPARSECONFIG_LIBS $LIB_CLOCK_GETTIME"
 fi
 
-### Reset below, after all checks for SuiteSparse libraries.
+## Save and restore LIBS after all checks for SuiteSparse libraries.
 suitesparse_save_LIBS="$LIBS"
 LIBS="$SUITESPARSECONFIG_LIBS $LIBS"
 
-### Check for AMD library
+### Check for AMD library.
 
 OCTAVE_CHECK_LIB(amd, AMD,
   [AMD library not found.  This will result in some lack of functionality for sparse matrices.],
@@ -2090,7 +2089,7 @@
   [amd_postorder],
   [], [don't use AMD library, disable some sparse matrix functionality])
 
-### Check for CAMD library
+### Check for CAMD library.
 
 OCTAVE_CHECK_LIB(camd, CAMD,
   [CAMD library not found.  This will result in some lack of functionality for sparse matrices.],
@@ -2098,7 +2097,7 @@
   [camd_postorder],
   [], [don't use CAMD library, disable some sparse matrix functionality])
 
-### Check for COLAMD library
+### Check for COLAMD library.
 
 OCTAVE_CHECK_LIB(colamd, COLAMD,
   [COLAMD library not found.  This will result in some lack of functionality for sparse matrices.],
@@ -2106,7 +2105,7 @@
   [colamd],
   [], [don't use COLAMD library, disable some sparse matrix functionality])
 
-### Check for CCOLAMD library
+### Check for CCOLAMD library.
 
 OCTAVE_CHECK_LIB(ccolamd, CCOLAMD,
   [CCOLAMD library not found.  This will result in some lack of functionality for sparse matrices.],
@@ -2115,8 +2114,8 @@
   [], [don't use CCOLAMD library, disable some sparse matrix functionality])
 
 ### Check for CHOLMOD library.
-### If your cholmod library requires cblas, then you will need to configure
-### with --with-cholmod="-lcholmod -lcblas".
+dnl If your cholmod library requires cblas, then you will need to configure
+dnl with --with-cholmod="-lcholmod -lcblas".
 
 save_LIBS="$LIBS"
 LIBS="$COLAMD_LDFLAGS $COLAMD_LIBS $AMD_LDFLAGS $AMD_LIBS $LAPACK_LIBS $BLAS_LIBS $FLIBS $LIBS"
@@ -2127,7 +2126,7 @@
   [], [don't use CHOLMOD library, disable some sparse matrix functionality])
 LIBS="$save_LIBS"
 
-### Check for SPQR library
+### Check for SPQR library.
 
 save_LIBS="$LIBS"
 LIBS="$CHOLMOD_LIBS $LIBS"
@@ -2138,7 +2137,7 @@
   [C++], [don't use SPQR library, disable some sparse matrix functionality])
 LIBS="$save_LIBS"
 
-### Check for CXSparse library
+### Check for CXSparse library.
 
 OCTAVE_CHECK_LIB(cxsparse, CXSparse,
   [CXSparse library not found.  This will result in some lack of functionality for sparse matrices.],
@@ -2194,7 +2193,7 @@
   [klu.h suitesparse/klu.h klu/klu.h], [klu_solve],
   [], [don't use KLU library, disable some sparse matrix functionality])
 
-### SUITESPARSECONFIG_LIBS added to LIBS above.
+## Restore LIBS after all suitesparse configuration tests
 LIBS="$suitesparse_save_LIBS"
 
 ## Collections of flags.
@@ -2264,11 +2263,11 @@
   LDFLAGS="$SUNDIALS_IDA_LDFLAGS $SUNDIALS_NVECSERIAL_LDFLAGS $KLU_LDFLAGS $BLAS_LDFLAGS $LDFLAGS"
   LIBS="$SUNDIALS_IDA_LIBS $SUNDIALS_NVECSERIAL_LIBS $KLU_LIBS $BLAS_LIBS $FLIBS $LIBS"
   if test -z "$warn_sundials_nvecserial" && test -z "$warn_sundials_ida"; then
-    dnl Any of the following tests could determine that SUNDIALS is incompatible
-    dnl and should be disabled. In that event, they all populate the same
-    dnl variable with appropriate warning messages, and further tests should be
-    dnl skipped if a warning message has already been generated that SUNDIALS is
-    dnl disabled.
+    dnl Any of the following tests could determine that SUNDIALS is
+    dnl incompatible and should be disabled.  In that event, they all populate
+    dnl the same variable with appropriate warning messages, and further tests
+    dnl should be skipped if a warning message has already been generated that
+    dnl SUNDIALS is disabled.
     warn_sundials_disabled=
     if test -z "$warn_sundials_disabled"; then
       OCTAVE_CHECK_SUNDIALS_COMPATIBLE_API
@@ -2293,7 +2292,7 @@
 dnl Define this way instead of with an #if in oct-conf-post-private.h so that
 dnl the build features script will get the correct value.
 dnl
-dnl The test on the sunlinsol_klu.h header is a bit of a kluge.
+dnl FIXME: The test on the sunlinsol_klu.h header is a bit of a kluge.
 dnl How can we do a better job here?  Do we need to disable sundials
 dnl any tests fail, or can we fix __ode15__.cc so that it still partially
 dnl works when some things are missing (for example, KLU)?
@@ -2429,7 +2428,7 @@
       ## Under Win32 platform, we want JAVA_HOME to be in MSYS format; that is,
       ## without colon and backslashes, as it is also used as path separator.
       ## Use quoted paths as Java may be installed in a path with whitespaces
-      ## (e.g. C:\Program Files\Java\...).
+      ## (e.g., C:\Program Files\Java\...).
       if test -n "$JAVA_HOME"; then
         JAVA_HOME=`cd "$JAVA_HOME" && pwd`
       fi
@@ -2468,7 +2467,7 @@
   fi
 
   ## At this point Win32 systems have enough configuration data.
-  ## We assume that all appropriate variables (e.g. INCLUDE and LIB) already
+  ## We assume that all appropriate variables (e.g., INCLUDE and LIB) already
   ## contain the required paths to compile and link against JDK.
   case $host_os in
     msdosmsvc)
@@ -2686,11 +2685,11 @@
 install_build_logs=no
 AC_ARG_ENABLE([install-build-logs],
   [AS_HELP_STRING([--enable-install-build-logs],
-    [install build logs (i.e. config.log) with Octave])],
+    [install build logs (i.e., config.log) with Octave])],
   [if test "$enableval" = yes; then install_build_logs=yes; fi])
 AM_CONDITIONAL([AMCOND_INSTALL_BUILD_LOGS], [test $install_build_logs = yes])
 
-### Determine whether libraries should be linked with visibility attributes
+### Determine whether libraries should be linked with visibility attributes.
 
 ENABLE_LIB_VISIBILITY_FLAGS=yes
 AC_ARG_ENABLE(lib-visibility-flags,
@@ -2728,7 +2727,7 @@
 AM_CONDITIONAL([AMCOND_LIB_VISIBILITY_FLAGS],
   [test $ENABLE_LIB_VISIBILITY_FLAGS = yes])
 
-### Set flags for symbol visibility
+### Set flags for symbol visibility.
 
 if test $ENABLE_LIB_VISIBILITY_FLAGS = yes; then
   EXTERNAL_DLL_DEFS="-DEXTERNAL_DLL"
@@ -2908,13 +2907,13 @@
       [Define to 1 if compiler supports -Wimplicit-fallthrough warning])])
 fi
 
-### These are recommended by the gnulib bootstrap script:
+### Recommendations from the gnulib bootstrap script.
 
 GNULIB_LINK_DEPS="$FREXPF_LIBM $FREXP_LIBM $GETHOSTNAME_LIB $LIBSOCKET $LIB_CLOCK_GETTIME $LIB_CRYPTO $LIB_GETLOGIN $LIB_NANOSLEEP $LIB_SELECT $LTLIBICONV $LTLIBINTL $LTLIBTHREAD $INTL_MACOSX_LIBS"
 
-### FIXME: This is a kluge to transform $libdir/libiconv.dll.a to -liconv.
-### It would probably be better to fix gnulib to not give us an absolute
-### file name...
+## FIXME: This is a kluge to transform $libdir/libiconv.dll.a to -liconv.
+## It would probably be better to fix gnulib to not give us an absolute
+## file name...
 
 case $host_os in
   mingw*)
@@ -2932,6 +2931,8 @@
 
 AC_SUBST(GNULIB_LINK_DEPS)
 
+### Set variables for link dependencies and options.
+
 BASE_LIBOCTAVE_LINK_DEPS="$CURL_LIBS $SPARSE_XLIBS $ARPACK_LIBS $QRUPDATE_LIBS $FFTW_XLIBS $LAPACK_LIBS $BLAS_LIBS $READLINE_LIBS $TERM_LIBS $LIBGLOB $PCRE_LIBS $DL_LIBS $PTHREAD_LIBS $FLIBS $LIBS"
 
 LIBOCTAVE_LINK_DEPS="$BASE_LIBOCTAVE_LINK_DEPS $GNULIB_LINK_DEPS"
@@ -3020,9 +3021,9 @@
 AC_SUBST(OCTAVE_GUI_LINK_OPTS)
 
 ##############################################################################
-### Configuration tests done
-
-### Restore original compilation flags
+### Configuration tests done.
+
+### Restore original compilation flags.
 CFLAGS="$original_octave_configure_CFLAGS"
 CXXFLAGS="$original_octave_configure_CXXFLAGS"