From 6169015de81eaa4f8148d29abcd640b4f4ab1b56 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Mon, 11 Mar 2013 14:51:33 -0600 Subject: [PATCH] regex: port to mingw's recent addition of undeclared alarm On mingw (at least, when cross-compiling with Fedora 18's mingw32-headers-2.0.999-0.15.trunk.20121110.fc18.noarch build), compilation of test-regex fails: test-regex.c: In function 'main': test-regex.c:42:11: error: 'SIGALRM' undeclared (first use in this function) test-regex.c:42:11: note: each undeclared identifier is reported only once for each function it appears in test-regex.c:43:3: warning: implicit declaration of function 'alarm' It turns out that recent mingw64 added an export of alarm() and SIGALRM, but guarded their declarations behind __USE_MINGW_ALARM (default off, and with alarm() only in the non-standard ); so the m4 tests were setting HAVE_ALARM to 1 based on link success but then failing to compile. * doc/posix-functions/alarm.texi (alarm): Document that alarm exists but still doesn't work in newer mingw. * m4/frexp.m4 (gl_FUNC_FREXP_WORKS): Check for alarm declaration, not existence. Ensure SIGALRM is not trapped. * m4/mktime.m4 (gl_FUNC_MKTIME): Likewise. * m4/regex.m4 (gl_REGEX): Likewise. * m4/remainderf.m4 (gl_FUNC_REMAINDERF_WORKS): Likewise. * tests/test-regex.c (main): Use correct probe for alarm. Signed-off-by: Eric Blake --- ChangeLog | 10 ++++++++++ doc/posix-functions/alarm.texi | 12 +++++++++++- m4/frexp.m4 | 10 ++++++---- m4/mktime.m4 | 11 +++++++---- m4/regex.m4 | 8 ++++---- m4/remainderf.m4 | 10 ++++++---- tests/test-regex.c | 4 ++-- 7 files changed, 46 insertions(+), 19 deletions(-) diff --git a/ChangeLog b/ChangeLog index 6d8c2c7ba..addadee95 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,15 @@ 2013-03-11 Eric Blake + regex: port to mingw's recent addition of undeclared alarm + * doc/posix-functions/alarm.texi (alarm): Document that alarm + exists but still doesn't work in newer mingw. + * m4/frexp.m4 (gl_FUNC_FREXP_WORKS): Check for alarm declaration, + not existence. Ensure SIGALRM is not trapped. + * m4/mktime.m4 (gl_FUNC_MKTIME): Likewise. + * m4/regex.m4 (gl_REGEX): Likewise. + * m4/remainderf.m4 (gl_FUNC_REMAINDERF_WORKS): Likewise. + * tests/test-regex.c (main): Use correct probe for alarm. + putenv: avoid compilation warning on mingw * lib/putenv.c (_unsetenv): Protect variable declaration. (putenv): Fix indentation. diff --git a/doc/posix-functions/alarm.texi b/doc/posix-functions/alarm.texi index 79d2db140..2a6c4f22f 100644 --- a/doc/posix-functions/alarm.texi +++ b/doc/posix-functions/alarm.texi @@ -13,6 +13,16 @@ Portability problems fixed by Gnulib: Portability problems not fixed by Gnulib: @itemize @item +This function has no impact if SIGALRM is inherited as +ignored; programs should use signal (SIGALRM, SIG_DFL) if +it is important to ensure the alarm will fire. +@item +Use of this function in multi-threaded applications is not advised. +@item This function is missing on some platforms: -mingw, MSVC 9. +mingw (2011), MSVC 9. +@item +This function is conditionally declared in the non-standard +@code{} header on some platforms: +mingw (2012 or newer). @end itemize diff --git a/m4/frexp.m4 b/m4/frexp.m4 index 39097923e..2eb98a1dc 100644 --- a/m4/frexp.m4 +++ b/m4/frexp.m4 @@ -1,4 +1,4 @@ -# frexp.m4 serial 14 +# frexp.m4 serial 15 dnl Copyright (C) 2007-2013 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -93,7 +93,7 @@ AC_DEFUN([gl_FUNC_FREXP_WORKS], [ AC_REQUIRE([AC_PROG_CC]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles - AC_CHECK_FUNCS_ONCE([alarm]) + AC_CHECK_DECLS_ONCE([alarm]) AC_CACHE_CHECK([whether frexp works], [gl_cv_func_frexp_works], [ AC_RUN_IFELSE( @@ -101,7 +101,8 @@ AC_DEFUN([gl_FUNC_FREXP_WORKS], #include #include #include -#if HAVE_ALARM +#if HAVE_DECL_ALARM +# include # include #endif /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0. @@ -124,9 +125,10 @@ int main() int i; volatile double x; double zero = 0.0; -#if HAVE_ALARM +#if HAVE_DECL_ALARM /* NeXTstep 3.3 frexp() runs into an endless loop when called on an infinite number. Let the test fail in this case. */ + signal (SIGALRM, SIG_DFL); alarm (5); #endif /* Test on denormalized numbers. */ diff --git a/m4/mktime.m4 b/m4/mktime.m4 index d3d376a4e..ab612abb7 100644 --- a/m4/mktime.m4 +++ b/m4/mktime.m4 @@ -1,4 +1,4 @@ -# serial 24 +# serial 25 dnl Copyright (C) 2002-2003, 2005-2007, 2009-2013 Free Software Foundation, dnl Inc. dnl This file is free software; the Free Software Foundation @@ -14,7 +14,7 @@ AC_DEFUN([gl_FUNC_MKTIME], dnl We don't use AC_FUNC_MKTIME any more, because it is no longer maintained dnl in Autoconf and because it invokes AC_LIBOBJ. AC_CHECK_HEADERS_ONCE([unistd.h]) - AC_CHECK_FUNCS_ONCE([alarm]) + AC_CHECK_DECLS_ONCE([alarm]) AC_REQUIRE([gl_MULTIARCH]) if test $APPLE_UNIVERSAL_BUILD = 1; then # A universal build on Apple Mac OS X platforms. @@ -34,8 +34,8 @@ AC_DEFUN([gl_FUNC_MKTIME], # include #endif -#ifndef HAVE_ALARM -# define alarm(X) /* empty */ +#ifndef HAVE_DECL_ALARM +# include #endif /* Work around redefinition to rpl_putenv by other config tests. */ @@ -171,10 +171,13 @@ main () int time_t_signed_magnitude = (time_t) ~ (time_t) 0 < (time_t) -1; int time_t_signed = ! ((time_t) 0 < (time_t) -1); +#if HAVE_DECL_ALARM /* This test makes some buggy mktime implementations loop. Give up after 60 seconds; a mktime slower than that isn't worth using anyway. */ + signal (SIGALRM, SIG_DFL); alarm (60); +#endif time_t_max = (! time_t_signed ? (time_t) -1 diff --git a/m4/regex.m4 b/m4/regex.m4 index ae89e3113..3334c1041 100644 --- a/m4/regex.m4 +++ b/m4/regex.m4 @@ -1,4 +1,4 @@ -# serial 63 +# serial 64 # Copyright (C) 1996-2001, 2003-2013 Free Software Foundation, Inc. # @@ -27,7 +27,7 @@ AC_DEFUN([gl_REGEX], # following run test, then default to *not* using the included regex.c. # If cross compiling, assume the test would fail and use the included # regex.c. - AC_CHECK_FUNCS_ONCE([alarm]) + AC_CHECK_DECLS_ONCE([alarm]) AC_CACHE_CHECK([for working re_compile_pattern], [gl_cv_func_re_compile_pattern_working], [AC_RUN_IFELSE( @@ -37,7 +37,7 @@ AC_DEFUN([gl_REGEX], #include #include #include - #if HAVE_ALARM + #if HAVE_DECL_ALARM # include # include #endif @@ -49,7 +49,7 @@ AC_DEFUN([gl_REGEX], const char *s; struct re_registers regs; -#if HAVE_ALARM +#if HAVE_DECL_ALARM /* Some builds of glibc go into an infinite loop on this test. */ signal (SIGALRM, SIG_DFL); alarm (2); diff --git a/m4/remainderf.m4 b/m4/remainderf.m4 index 33df781c8..afb26181f 100644 --- a/m4/remainderf.m4 +++ b/m4/remainderf.m4 @@ -1,4 +1,4 @@ -# remainderf.m4 serial 7 +# remainderf.m4 serial 8 dnl Copyright (C) 2012-2013 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -150,13 +150,14 @@ AC_DEFUN([gl_FUNC_REMAINDERF_WORKS], [ AC_REQUIRE([AC_PROG_CC]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles - AC_CHECK_FUNCS_ONCE([alarm]) + AC_CHECK_DECLS_ONCE([alarm]) AC_CACHE_CHECK([whether remainderf works], [gl_cv_func_remainderf_works], [ AC_RUN_IFELSE( [AC_LANG_SOURCE([[ #include -#if HAVE_ALARM +#if HAVE_DECL_ALARM +# include # include #endif extern @@ -169,7 +170,8 @@ volatile float y; float z; int main () { -#if HAVE_ALARM +#if HAVE_DECL_ALARM + signal (SIGALRM, SIG_DFL); alarm (5); #endif /* This test fails on IRIX 6.5. */ diff --git a/tests/test-regex.c b/tests/test-regex.c index 2488cee21..682903557 100644 --- a/tests/test-regex.c +++ b/tests/test-regex.c @@ -21,7 +21,7 @@ #include #include #include -#if HAVE_ALARM +#if HAVE_DECL_ALARM # include # include #endif @@ -36,7 +36,7 @@ main (void) const char *s; struct re_registers regs; -#if HAVE_ALARM +#if HAVE_DECL_ALARM /* Some builds of glibc go into an infinite loop on this test. */ int alarm_value = 2; signal (SIGALRM, SIG_DFL); -- 2.11.0