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[[!meta title="Hiccups of Git"]]
[[!tag open_issue_porting]]
[[!toc]]
# Log
December, 2008.
On the otherwise-idle flubber:
$ git clone git://sources.redhat.com/git/glibc.git
Initialized empty Git repository in /media/data/home/tschwinge/tmp/glibc/glibc/.git/
remote: Generating pack...
remote: Done counting 380933 objects.
remote: Deltifying 380933 objects...
remote: 100% (380933/380933) done
remote: Total 380933 (delta 294166), reused 380686 (delta 294002)
Receiving objects: 100% (380933/380933), 70.31 MiB | 27 KiB/s, done.
Resolving deltas: 100% (294166/294166), done.
error: git-checkout-index: unable to create file iconvdata/ibm1122.c (Interrupted system call)
error: git-checkout-index: unable to create file localedata/charmaps/IBM862 (Interrupted system call)
Checking out files: 100% (10676/10676), done.
$ git status
# On branch master
# Changed but not updated:
# (use "git add <file>..." to update what will be committed)
#
# modified: iconvdata/ibm1122.c
# modified: localedata/charmaps/IBM862
#
no changes added to commit (use "git add" and/or "git commit -a")
$ ls -l iconvdata/ibm1122.c localedata/charmaps/IBM862
-rw-r--r-- 1 tschwinge tschwinge 0 2008-12-15 15:49 iconvdata/ibm1122.c
-rw-r--r-- 1 tschwinge tschwinge 0 2008-12-15 15:49 localedata/charmaps/IBM862
So these files are indeed of zero-length in the checked-out tree. Is this
Git's fault or something else's?
Fixing this situation is easy enough:
$ git checkout -- iconvdata/ibm1122.c localedata/charmaps/IBM862
$ git status
# On branch master
nothing to commit (working directory clean)
Still seen on 2010-03-16.
---
A very similar issue, seen on 2010-11-17. The working tree had a lot of
differences to HEAD.
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
error: unable to unlink old 'gcc/config/darwin.h' (Interrupted system call)
Checking out files: 100% (1149/1149), done.
fatal: Could not reset index file to revision 'HEAD'.
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
error: unable to unlink old 'gcc/config/iq2000/iq2000.md' (Interrupted system call)
error: git checkout-index: unable to create file gcc/config/lm32/lm32.c (File exists)
Checking out files: 100% (1149/1149), done.
fatal: Could not reset index file to revision 'HEAD'.
tschwinge@grubber:~/tmp/gcc/hurd $ ls -l gcc/config/iq2000/iq2000.md gcc/config/lm32/lm32.c
ls: cannot access gcc/config/iq2000/iq2000.md: No such file or directory
-rw-r--r-- 1 tschwinge tschwinge 32159 Nov 17 19:09 gcc/config/lm32/lm32.c
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
error: git checkout-index: unable to create file gcc/fortran/expr.c (Interrupted system call)
Checking out files: 100% (1149/1149), done.
fatal: Could not reset index file to revision 'HEAD'.
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
error: git checkout-index: unable to create file gcc/config/sol2.h (Interrupted system call)
Checking out files: 100% (1149/1149), done.
fatal: Could not reset index file to revision 'HEAD'.
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
error: unable to unlink old 'gcc/config/i386/i386.c' (Interrupted system call)
Checking out files: 100% (1149/1149), done.
fatal: Could not reset index file to revision 'HEAD'.
tschwinge@grubber:~/tmp/gcc/hurd $ git reset --hard HEAD
Checking out files: 100% (1149/1149), done.
HEAD is now at fe3e43c Merge commit 'refs/top-bases/hurd/master' into hurd/master
---
2010-12-22, grubber:
$ git remote update
Fetching savannah
remote: Counting objects: 582331, done.
remote: Compressing objects: 100% (124133/124133), done.
remote: Total 582331 (delta 460856), reused 578352 (delta 457598)
Receiving objects: 100% (582331/582331), 525.15 MiB | 204 KiB/s, done.
fatal: cannot pread pack file: Interrupted system call
fatal: index-pack failed
error: Could not fetch savannah
---
2011-06-10, coulomb.SCHWINGE, checking out [[binutils]]' master branch,
starting from an empty working directory (after an external `git push`):
$ git checkout -f
fatal: cannot create directory at 'gas/testsuite/gas/bfin': Interrupted system call
$ git checkout -f
error: unable to create file gas/testsuite/gas/i386/ilp32/x86-64-sse4_1-intel.d (File exists)
warning: unable to unlink gas/testsuite/gas/m68k-coff: Operation not permitted
fatal: cannot create directory at 'gas/testsuite/gas/m68k-coff': Operation not permitted
$ git checkout -f
error: unable to create file gas/testsuite/gas/h8300/h8300.exp (File exists)
error: unable to create file gas/testsuite/gas/i386/x86-64-addr32-intel.d (File exists)
error: unable to create file gas/testsuite/gas/ia64/secname.d (File exists)
error: unable to create file gas/testsuite/gas/m68k/pr11676.s (File exists)
Checking out files: 100% (12315/12315), done.
$ git status
# On branch master
# Changes not staged for commit:
# (use "git add <file>..." to update what will be committed)
# (use "git checkout -- <file>..." to discard changes in working directory)
#
# modified: gas/testsuite/gas/h8300/h8300.exp
# modified: gas/testsuite/gas/i386/x86-64-addr32-intel.d
# modified: gas/testsuite/gas/ia64/secname.d
# modified: gas/testsuite/gas/m68k/pr11676.s
#
no changes added to commit (use "git add" and/or "git commit -a")
$ rm gas/testsuite/gas/h8300/h8300.exp gas/testsuite/gas/i386/x86-64-addr32-intel.d gas/testsuite/gas/ia64/secname.d gas/testsuite/gas/m68k/pr11676.s
$ git checkout -f
$ git status
# On branch master
nothing to commit (working directory clean)
# Analysis
2011-06-13
Running `git checkout -f` under GDB:
error: git checkout-index: unable to create file gas/testsuite/gas/cris/string-1.s (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/i386/x86-64-sse-check.d (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/i386/x86-64-sse4_1.d (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/ppc/astest.d (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/tic6x/reloc-bad-4.s (File exists)
warning: unable to unlink include/cgen: Operation not permitted
fatal: cannot create directory at 'include/cgen': Operation not permitted
Again:
error: git checkout-index: unable to create file gas/config/te-vxworks.h (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/cris/string-1.s (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/d10v/warning-019.s (File exists)
error: git checkout-index: unable to create file gas/testsuite/gas/i860/dual03.s (File exists)
error: git checkout-index: unable to create file ld/testsuite/ld-mmix/sec-7a.s (File exists)
warning: unable to unlink ld/testsuite/ld-powerpc: Operation not permitted
fatal: cannot create directory at 'ld/testsuite/ld-powerpc': Operation not permitted
And: [[git_duplicated_content]].
All these (very likely) have the same root cause: `SA_RESTART` restarting too
much.
With `git checkout`, Git uses in progress.c a SIGALRM handler (`SA_RESTART`;
invoked every second via `setitimer(ITIMER_REAL)`) to display status messages:
*x % already checked out*.
To avoid the status update signals every second, in
`[git]/progress.c:start_progress_delay` we can just return `NULL` (manually in
GDB, for example), then both the *error: git checkout-index* and the
[[duplicated content|git_duplicated_content]] issues go away.
I'm guessing that when returning from a `SA_RESTART` signal handler, too much
of the \`\`syscall''s is being restarted. For example, if a file has already
been created, the restarted creation attempt would fail: *File exists*. If
data has been written, it might get written again (duplication issue). Then,
there are cases where `unlink` apparently returns EINTR, which is not kosher
either. Etc.
Do we have problems with `SA_RESTART` vs. the atomicity of our syscall-alikes?