Change Details

When _ISOC11_SOURCES is defined for glibc at the same time __POSIX_C_SOURCE is defined, it extends the __POSIX_C_SOURCE definition by exaclty what C11 adds to the spec for each of the affected headers. It goes one step further by doing this by default when C11 or higher compliation mode is selected. There's a diversity of opinion about whether this automatic extension is standards conformant, so only enable C11 visibility when specifically requested since the Open Group standard allows this when other feature macros are defined by other standards. Should POSIX clarify this in the future, it would be easy enough to correct. PR: 255290 Sponsored by: Netflix

When _ISOC11_SOURCES is defined for glibc at the same time __POSIX_C_SOURCE is defined, it extends the __POSIX_C_SOURCE definition by exaclty what C11 adds to the spec for each of the affected headers. It goes one step further by doing this by default when C11 or higher compliation mode is selected. There's a diversity of opinion about whether this automatic extension is standards conformant, so only enable C11 visibility when specifically requested since the Open Group standard allows this when other feature macros are defined by other standards. Should POSIX clarify this in the future, it would be easy enough to correct. This will allow easier porting of software that's taking advantage of the automatic enabling since it's not now possible at all. PR: 255290 Sponsored by: Netflix

When _ISOC11_SOURCES is defined for glibc at the same time __POSIX_C_SOURCE is defined, it extends the __POSIX_C_SOURCE definition by exaclty what C11 adds to the spec for each of the affected headers. It goes one step further by doing this by default when C11 or higher compliation mode is selected. There's a diversity of opinion about whether this automatic extension is standards conformant, so only enable C11 visibility when specifically requested since the Open Group standard allows this when other feature macros are defined by other standards. Should POSIX clarify this in the future, it would be easy enough to correct. This will allow easier porting of software that's taking advantage of the automatic enabling since it's not now possible at all. PR: 255290 Sponsored by: Netflix