git-http-fetch segfault, curl 7.18.0

Hi, as reported through http://bugs.debian.org/468836, I can reproduce with current maint branch on Debian/unstable, but I don't know whether it's a problem in curl, or in git. Maybe anyone with some experience in curl can help on this?

 $ make
 [...]
 $ mkdir repo && cd repo && git init
 Initialized empty Git repository in .git/
 $ ../git-http-fetch -v -a -w remotes/origin/master ef227a3da916f53f5a9ef4266c27c283c1ab607b http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 got ef227a3da916f53f5a9ef4266c27c283c1ab607b
 walk ef227a3da916f53f5a9ef4266c27c283c1ab607b
 got 12d086d13b3e69b26389282fe031b1a15153d84c
 Getting alternates list for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Getting pack list for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 got e25c7e03ea0c0d4d9bea5552ee629a25196ff43f
 got a8d762c979ac21da092732eafb6ded8751c3f63d
 Getting index for pack 06eec8e3e8f770e471d5f3f19c3b8ffa9159fd97
 got 31cdb53945ddfa3b7bc15e12fdf900024eec1a56
 Getting pack 06eec8e3e8f770e471d5f3f19c3b8ffa9159fd97
  which contains 64580202061d4d8f449e09107ac6e60706142202
 walk 64580202061d4d8f449e09107ac6e60706142202
 error: Unable to find 30e8500073c101f656311906f5a00f0ccc0e8546 under http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Cannot obtain needed commit 30e8500073c101f656311906f5a00f0ccc0e8546
 while processing commit 64580202061d4d8f449e09107ac6e60706142202.
 $ echo $?
 255
 $ ../git-http-fetch -v -a -w remotes/origin/master ef227a3da916f53f5a9ef4266c27c283c1ab607b http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 walk ef227a3da916f53f5a9ef4266c27c283c1ab607b
 walk 64580202061d4d8f449e09107ac6e60706142202
 Getting alternates list for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Getting pack list for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 error: Unable to find 30e8500073c101f656311906f5a00f0ccc0e8546 under
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Cannot obtain needed commit 30e8500073c101f656311906f5a00f0ccc0e8546
 while processing commit 64580202061d4d8f449e09107ac6e60706142202.
 Waiting for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/8b/d9d5f451cb08435cdcb773dc8cdddf9f61d553
 Waiting for
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/ef/b3c1b344b887ffdb5d917eca2a28e5f176613c
 Segmentation fault

gdb gives this

 (gdb) r -v -a -w remotes/origin/master ef227a3da916f53f5a9ef4266c27c283c1ab607b http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 Starting program: /usr/local/src/Debian/GIT/git/git-http-fetch -v -a -w
 remotes/origin/master  ef227a3da916f53f5a9ef4266c27c283c1ab607b
 http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 [Thread debugging using libthread_db enabled]
 walk ef227a3da916f53f5a9ef4266c27c283c1ab607b
 [New Thread 0x3002c220 (LWP 19305)]
 walk 64580202061d4d8f449e09107ac6e60706142202
 Getting alternates list for http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Getting pack list for http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 error: Unable to find 30e8500073c101f656311906f5a00f0ccc0e8546 under http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Cannot obtain needed commit 30e8500073c101f656311906f5a00f0ccc0e8546
 while processing commit 64580202061d4d8f449e09107ac6e60706142202.
 Waiting for http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/8b/d9d5f451cb08435cdcb773dc8cdddf9f61d553
 Waiting for http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/3a/36bcfe419fe97021a330516c25e8c8d6a61b23
 Waiting for http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/f9/1f9480407a3786f0a66855af7c64da9360c214

 Program received signal SIGSEGV, Segmentation fault.
 [Switching to Thread 0x3002c220 (LWP 19305)]
 0x0ffbaddc in ?? () from /usr/lib/libcurl-gnutls.so.4
 (gdb) bt
 #0  0x0ffbaddc in ?? () from /usr/lib/libcurl-gnutls.so.4
 #1  0x0ffbadc4 in ?? () from /usr/lib/libcurl-gnutls.so.4
 #2  0x0ffc3f0c in curl_easy_cleanup () from /usr/lib/libcurl-gnutls.so.4
 #3  0x100a4e8c in fill_active_slots () at http.c:442
 #4  0x100a5100 in step_active_slots () at http.c:459
 #5  0x100a519c in run_active_slot (slot=0x10169f08) at http.c:479
 #6  0x100a5478 in http_cleanup () at http.c:296
 #7  0x100a6514 in cleanup (walker=<value optimized out>) at http-walker.c:900
 #8  0x100a2550 in walker_free (walker=<value optimized out>) at walker.c:315
 #9  0x1004df68 in cmd_http_fetch (argc=<value optimized out>, argv=0x7fbfe784, 
     prefix=<value optimized out>) at builtin-http-fetch.c:81
 #10 0x100045e8 in handle_internal_command (argc=7, argv=0x7fbfe784) at git.c:259
 #11 0x10004f88 in main (argc=7, argv=0x7fbfe784) at git.c:420
 (gdb) 

and sometimes

 (gdb) r -v -a -w remotes/origin/master ef227a3da916f53f5a9ef4266c27c283c1ab607b http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 Starting program: /usr/local/src/Debian/GIT/git/git-http-fetch -v -a -w remotes/origin/master  ef227a3da916f53f5a9ef4266c27c283c1ab607b http://git.debian.org/git/users/eddyp-guest/test-segfault.git/
 [Thread debugging using libthread_db enabled]
 walk ef227a3da916f53f5a9ef4266c27c283c1ab607b
 [New Thread 0x3002c220 (LWP 20097)]
 walk 64580202061d4d8f449e09107ac6e60706142202
 Getting alternates list for http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Getting pack list for http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 error: Unable to find 30e8500073c101f656311906f5a00f0ccc0e8546 under http://git.debian.org/git/users/eddyp-guest/test-segfault.git
 Cannot obtain needed commit 30e8500073c101f656311906f5a00f0ccc0e8546
 while processing commit 64580202061d4d8f449e09107ac6e60706142202.
 Waiting for http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/61/6e4145cf75c474bafa94f1dd917ed0a6f421fc
 Waiting for http://git.debian.org/git/users/eddyp-guest/test-segfault.git/objects/ef/b3c1b344b887ffdb5d917eca2a28e5f176613c

 Program received signal SIGSEGV, Segmentation fault.
 [Switching to Thread 0x3002c220 (LWP 20097)]
 fill_active_slots () at http.c:441
 441                     if (!slot->in_use && slot->curl != NULL) {
 (gdb) 

Thanks, Gerrit.