Problems building rsync with Clang 15 beta
Paul Eggert <[email protected]>
| Newsgroups | gmane.comp.sysutils.autoconf.patches,gmane.network.rsync.general |
|---|---|
| Organization | UCLA Computer Science Department |
| Message-ID | <[email protected]> |
On 8/17/22 23:58, Khem Raj wrote: > rsync which add -pedantic-errors option to cflags during configure OK, that's the problem then. 'configure' should not use flags like -pedantic-errors. This has long been a property of 'autoconf'-generated scripts. The simplest way to fix this would be for rsync to not add -pedantic-errors, as it's more trouble than it's worth. If rsync must add -pedantic-errors for some reason, it should do so at the very end of 'configure', as in the attached untested patch, so as not to screw up earlier 'configure' tests; and perhaps it'd be better for rsync to also add -pedantic-errors only for GCC not Clang (since Clang is more likely to mutate further in this area). Really, though, omitting -pedantic-errors entirely is the way to go. -pedantic-errors should be enabled only for special purposes, by explicit request of the person running 'configure' and/or 'make'; it's not suitable as a default option. Anyway, please give this rsync patch a try. I'll cc it to the rsync mailing list to give rsync developers a heads-up about the compatibility problem building rsync with Clang 15 (which luckily does not exist yet :-).
0001-Turn-on-pedantic-errors-at-the-end-of-configure.patch
(text/x-patch, 2.5 KB)
From e64a58387db46239902b610871a0eb81626e99ff Mon Sep 17 00:00:00 2001 From: Paul Eggert <[email protected]> Date: Thu, 18 Aug 2022 07:46:28 -0700 Subject: [PATCH] Turn on -pedantic-errors at the end of 'configure' Problem reported by Khem Raj in: https://lists.gnu.org/r/autoconf-patches/2022-08/msg00009.html --- configure.ac | 35 ++++++++++++++++++++--------------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/configure.ac b/configure.ac index d185b2d3..7e9514f7 100644 --- a/configure.ac +++ b/configure.ac @@ -1071,21 +1071,6 @@ elif test x"$ac_cv_header_popt_h" != x"yes"; then with_included_popt=yes fi -if test x"$GCC" = x"yes"; then - if test x"$with_included_popt" != x"yes"; then - # Turn pedantic warnings into errors to ensure an array-init overflow is an error. - CFLAGS="$CFLAGS -pedantic-errors" - else - # Our internal popt code cannot be compiled with pedantic warnings as errors, so try to - # turn off pedantic warnings (which will not lose the error for array-init overflow). - # Older gcc versions don't understand -Wno-pedantic, so check if --help=warnings lists - # -Wpedantic and use that as a flag. - case `$CC --help=warnings 2>/dev/null | grep Wpedantic` in - *-Wpedantic*) CFLAGS="$CFLAGS -pedantic-errors -Wno-pedantic" ;; - esac - fi -fi - AC_MSG_CHECKING([whether to use included libpopt]) if test x"$with_included_popt" = x"yes"; then AC_MSG_RESULT($srcdir/popt) @@ -1444,6 +1429,26 @@ case "$CC" in ;; esac +# Enable -pedantic-errors last, so that it doesn't mess up other +# 'configure' tests. For example, Autoconf uses empty function +# prototypes like 'int main () {}' which Clang 15's -pedantic-errors +# would reject. Generally it's not a good idea to try to run +# 'configure' itself with strict compiler checking. +if test x"$GCC" = x"yes"; then + if test x"$with_included_popt" != x"yes"; then + # Turn pedantic warnings into errors to ensure an array-init overflow is an error. + CFLAGS="$CFLAGS -pedantic-errors" + else + # Our internal popt code cannot be compiled with pedantic warnings as errors, so try to + # turn off pedantic warnings (which will not lose the error for array-init overflow). + # Older gcc versions don't understand -Wno-pedantic, so check if --help=warnings lists + # -Wpedantic and use that as a flag. + case `$CC --help=warnings 2>/dev/null | grep Wpedantic` in + *-Wpedantic*) CFLAGS="$CFLAGS -pedantic-errors -Wno-pedantic" ;; + esac + fi +fi + AC_CONFIG_FILES([Makefile lib/dummy zlib/dummy popt/dummy shconfig]) AC_OUTPUT -- 2.37.1