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| author | Joseph Myers <joseph@codesourcery.com> | 2018-11-27 22:05:49 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2018-11-27 22:05:49 +0000 |
| commit | b473b7d88e6829fd0c8a02512b86950dc7089039 (patch) | |
| tree | dd7007dc040720463965c760456092e91fc07433 /sysdeps/mach | |
| parent | c74a91deaa5de416237c02bbb3e41bda76ca4c7b (diff) | |
| download | glibc-b473b7d88e6829fd0c8a02512b86950dc7089039.tar.gz glibc-b473b7d88e6829fd0c8a02512b86950dc7089039.tar.xz glibc-b473b7d88e6829fd0c8a02512b86950dc7089039.zip | |
Fix Hurd build with read-only source directory.
The logic for generating sysdeps/mach/hurd/bits/errno.h involves a stamp file and $(move-if-change). The temporary file (generated unconditionally) is generated in the source directory. This means that even if sysdeps/mach/hurd/bits/errno.h is up to date, and has an up to date timestamp, the build will fail if the source directory is read-only. Even with a writable source directory, multiple concurrent builds for i686-gnu with the same source directory could race to access the temporary file (which always has the same name). This patch uses the build directory for the temporary file instead to avoid those problems. (In the case where the file is out of date and the temporary file does need to be moved to the source directory, if there are multiple concurrent builds for i686-gnu with the same source directory, and the source and build directories are on different filesystems, it's possible there might still be races replacing the file in the source directory, depending on exactly how mv handles such cross-filesystem moves. This is certainly no worse than the present situation, where such a case would have races regardless of whether the file is out of date or whether different filesystems are in use.) Tested with a build-many-glibcs.py build for i686-gnu. * sysdeps/mach/hurd/Makefile ($(common-objpfx)stamp-errnos): Use $(hurd-objpfx)bits/errno.h-tmp, not $(hurd)/bits/errno.h-tmp.
Diffstat (limited to 'sysdeps/mach')
| -rw-r--r-- | sysdeps/mach/hurd/Makefile | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sysdeps/mach/hurd/Makefile b/sysdeps/mach/hurd/Makefile index e15341ca8d..69f12d4efb 100644 --- a/sysdeps/mach/hurd/Makefile +++ b/sysdeps/mach/hurd/Makefile @@ -91,10 +91,11 @@ $(common-objpfx)errnos.d: $(mach-errnos-deps) $(hurd)/bits/errno.h: $(common-objpfx)stamp-errnos ; $(common-objpfx)stamp-errnos: $(hurd)/errnos.awk $(errno.texinfo) \ $(mach-errnos-deps) $(common-objpfx)errnos.d - $(AWK) -f $^ > $(hurd)/bits/errno.h-tmp + mkdir -p $(hurd-objpfx)bits + $(AWK) -f $^ > $(hurd-objpfx)bits/errno.h-tmp # Make it unwritable so noone will edit it by mistake. - -chmod a-w $(hurd)/bits/errno.h-tmp - $(move-if-change) $(hurd)/bits/errno.h-tmp $(hurd)/bits/errno.h + -chmod a-w $(hurd-objpfx)bits/errno.h-tmp + $(move-if-change) $(hurd-objpfx)bits/errno.h-tmp $(hurd)/bits/errno.h touch $@ common-generated += errnos.d stamp-errnos |