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b5891a57b5
AC_TYPE_GETGROUPS is the last remaining use of AC_EGREP_HEADER in stock Autoconf macros. It uses it only when cross compiling, as a fallback from an AC_RUN_IFELSE check, testing for a bug in system headers from the late 1980s or early 1990s, where gid_t *existed* but the second argument to getgroups needed to be an array of int, and this didn’t cause a compile error (i.e. the system headers declare getgroups with no prototype or an incorrect prototype). AC_FUNC_GETGROUPS also uses AC_RUN_IFELSE to test for obscure problems specific to long-obsolete Unixes. The downsides of AC_RUN_IFELSE and AC_EGREP_HEADER seem more severe than the chances of someone compiling a current-generation program, that uses getgroups, on an OS old enough to have one of the really nasty bugs. Accordingly, this patch changes AC_FUNC_GETGROUPS to use a host_os-based *blacklist* both in native and cross compilation. This is limited to the two host_os values for which either our old code, or Gnulib, documented a serious bug: ultrix* and nextstep*. Currently it does not try to pin down the exact version ranges subject to the bugs — that would require research by someone with access to the full history of these OSes. An incorrect guess by this blacklist can be overridden by setting ac_cv_func_getgroups_works in config.site. AC_TYPE_GETGROUPS, for its part, now does a series of regular old AC_COMPILE_IFELSE checks to probe the prototype of getgroups, and considers that good enough. While I was in there I noticed that AC_FUNC_GETGROUPS does not AC_SUBST a documented output variable, and that the name of this variable is misspelled in the manual. * lib/autoconf/functions.m4 (AC_FUNC_GETGROUPS): Use AC_SEARCH_LIBS to probe for getgroups. Use an AC_CANONICAL_HOST-based blacklist for bug detection, not AC_RUN_IFELSE. AC_SUBST the GETGROUPS_LIB output variable. * lib/autoconf/types.m4 (AC_TYPE_GETGROUPS): Check only the prototype of getgroups, using AC_COMPILE_IFELSE; do not use either AC_RUN_IFELSE or AC_EGREP_HEADER. * doc/autoconf.texi: Update to match. Correct misspelling of GETGROUPS_LIB. * tests.local.at (_AT_CHECK_ENV): Allow GETGROUPS_LIB output variable. |
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| .. | ||
| data | ||
| atlocal.in | ||
| autoscan.at | ||
| autotest.at | ||
| base.at | ||
| c.at | ||
| compile.at | ||
| erlang.at | ||
| foreign.at | ||
| fortran.at | ||
| go.at | ||
| local.at | ||
| local.mk | ||
| m4sh.at | ||
| m4sugar.at | ||
| mktests.pl | ||
| semantics.at | ||
| statesave.m4 | ||
| suite.at | ||
| tools.at | ||
| torture.at | ||
| wrapper.as | ||