diff options
| -rw-r--r-- | aclocal.m4 | 41 | ||||
| -rw-r--r-- | config.h.in | 4 | ||||
| -rwxr-xr-x | configure | 51 | ||||
| -rw-r--r-- | configure.in | 1 | ||||
| -rw-r--r-- | netdissect-stdinc.h | 6 |
5 files changed, 103 insertions, 0 deletions
@@ -1323,6 +1323,47 @@ fi AC_MSG_RESULT($ac_cv___attribute___noreturn_function_pointer) ]) +dnl +dnl Test whether __attribute__((fallthrough)) can be used without warnings +dnl + +AC_DEFUN(AC_C___ATTRIBUTE___FALLTHROUGH, [ +AC_MSG_CHECKING([whether __attribute__((fallthrough)) can be used without warnings]) +AC_CACHE_VAL(ac_cv___attribute___fallthrough, [ +save_CFLAGS="$CFLAGS" +CFLAGS="$CFLAGS $ac_lbl_cc_force_warning_errors" +AC_COMPILE_IFELSE([ + AC_LANG_SOURCE([[ +#include <stdio.h> + +int +main(int argc, char **argv) +{ + int x = 1; + switch (x) + { + case 1: + printf ("x == %d\n", x); + __attribute__ ((fallthrough)); + case 2: + printf ("x == %d\n", x); + break; + default: + return 0; + } + return x; +} + ]])], +ac_cv___attribute___fallthrough=yes, +ac_cv___attribute___fallthrough=no)]) +CFLAGS="$save_CFLAGS" +if test "$ac_cv___attribute___fallthrough" = "yes"; then + AC_DEFINE(__ATTRIBUTE___FALLTHROUGH_OK, 1, + [define if your compiler allows __attribute__((fallthrough)) without a warning]) +fi +AC_MSG_RESULT($ac_cv___attribute___fallthrough) +]) + AC_DEFUN(AC_LBL_SSLEAY, [ # diff --git a/config.h.in b/config.h.in index bbe1811b..6388afdc 100644 --- a/config.h.in +++ b/config.h.in @@ -331,6 +331,10 @@ #define below would cause a syntax error. */ #undef _UINT8_T +/* define if your compiler allows __attribute__((fallthrough)) without a + warning */ +#undef __ATTRIBUTE___FALLTHROUGH_OK + /* define if your compiler allows __attribute__((format)) without a warning */ #undef __ATTRIBUTE___FORMAT_OK @@ -3794,6 +3794,57 @@ fi $as_echo "$ac_cv___attribute___format_function_pointer" >&6; } fi + +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether __attribute__((fallthrough)) can be used without warnings" >&5 +$as_echo_n "checking whether __attribute__((fallthrough)) can be used without warnings... " >&6; } +if ${ac_cv___attribute___fallthrough+:} false; then : + $as_echo_n "(cached) " >&6 +else + +save_CFLAGS="$CFLAGS" +CFLAGS="$CFLAGS $ac_lbl_cc_force_warning_errors" +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + + +#include <stdio.h> + +int +main(int argc, char **argv) +{ + int x = 1; + switch (x) + { + case 1: + printf ("x == %d\n", x); + __attribute__ ((fallthrough)); + case 2: + printf ("x == %d\n", x); + break; + default: + return 0; + } + return x; +} + +_ACEOF +if ac_fn_c_try_compile "$LINENO"; then : + ac_cv___attribute___fallthrough=yes +else + ac_cv___attribute___fallthrough=no +fi +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext +fi + +CFLAGS="$save_CFLAGS" +if test "$ac_cv___attribute___fallthrough" = "yes"; then + +$as_echo "#define __ATTRIBUTE___FALLTHROUGH_OK 1" >>confdefs.h + +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv___attribute___fallthrough" >&5 +$as_echo "$ac_cv___attribute___fallthrough" >&6; } + fi ac_ext=c diff --git a/configure.in b/configure.in index 9b06fd92..a7b879fc 100644 --- a/configure.in +++ b/configure.in @@ -30,6 +30,7 @@ if test "$ac_cv___attribute__" = "yes"; then if test "$ac_cv___attribute___format" = "yes"; then AC_C___ATTRIBUTE___FORMAT_FUNCTION_POINTER fi + AC_C___ATTRIBUTE___FALLTHROUGH fi AC_CHECK_HEADERS(fcntl.h rpc/rpc.h rpc/rpcent.h netdnet/dnetdb.h) diff --git a/netdissect-stdinc.h b/netdissect-stdinc.h index c7070f0a..fb385fb9 100644 --- a/netdissect-stdinc.h +++ b/netdissect-stdinc.h @@ -401,4 +401,10 @@ struct in6_addr { #define max(a,b) ((b)>(a)?(b):(a)) #endif +#ifdef __ATTRIBUTE___FALLTHROUGH_OK +# define ND_FALL_THROUGH __attribute__ ((fallthrough)) +#else +# define ND_FALL_THROUGH +#endif /* __ATTRIBUTE___FALLTHROUGH_OK */ + #endif /* netdissect_stdinc_h */ |