| Message ID | 6de0089348765e60bcdf59ef5813d7bb631c967f.1566805721.git.ps@pks.im (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] mount: fix compilation if __GLIBC__ is not defined | expand |
On 8/26/19 3:48 AM, Patrick Steinhardt wrote: > As glibc versions before v2.24 couldn't safely include <linux/in6.h>, > commit 8af595b7 (mount: support compiling with old glibc, 2017-07-26) > introduced some preprocessor checks to special-case such old versions. > While there is a check whether __GLIBC__ is defined at all, it only > applies to the first comparison `__GLIBC__ < 2`, but doesn't apply to > the second check due to operator precedence. Thus the preprocessor may > use an undefined value and thus generate an error if __GLIBC__ is not > defined. > > Fix the issue by wrapping the version check in braces. > > Signed-off-by: Patrick Steinhardt <ps@pks.im> Commited.... steved. > --- > utils/mount/network.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/utils/mount/network.c b/utils/mount/network.c > index e166a823..6ac913d9 100644 > --- a/utils/mount/network.c > +++ b/utils/mount/network.c > @@ -39,7 +39,7 @@ > #include <sys/socket.h> > #include <sys/wait.h> > #include <sys/stat.h> > -#if defined(__GLIBC__) && (__GLIBC__ < 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 24) > +#if defined(__GLIBC__) && ((__GLIBC__ < 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 24)) > /* Cannot safely include linux/in6.h in old glibc, so hardcode the needed values */ > # define IPV6_PREFER_SRC_PUBLIC 2 > # define IPV6_ADDR_PREFERENCES 72 >
diff --git a/utils/mount/network.c b/utils/mount/network.c index e166a823..6ac913d9 100644 --- a/utils/mount/network.c +++ b/utils/mount/network.c @@ -39,7 +39,7 @@ #include <sys/socket.h> #include <sys/wait.h> #include <sys/stat.h> -#if defined(__GLIBC__) && (__GLIBC__ < 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 24) +#if defined(__GLIBC__) && ((__GLIBC__ < 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 24)) /* Cannot safely include linux/in6.h in old glibc, so hardcode the needed values */ # define IPV6_PREFER_SRC_PUBLIC 2 # define IPV6_ADDR_PREFERENCES 72
As glibc versions before v2.24 couldn't safely include <linux/in6.h>, commit 8af595b7 (mount: support compiling with old glibc, 2017-07-26) introduced some preprocessor checks to special-case such old versions. While there is a check whether __GLIBC__ is defined at all, it only applies to the first comparison `__GLIBC__ < 2`, but doesn't apply to the second check due to operator precedence. Thus the preprocessor may use an undefined value and thus generate an error if __GLIBC__ is not defined. Fix the issue by wrapping the version check in braces. Signed-off-by: Patrick Steinhardt <ps@pks.im> --- utils/mount/network.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)