Description:
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Note: PHP version is actually 5.3.6, but it wasn't a choice in the dropdown.

A segmentation fault is occurring when using APC_UPLOAD_PROGRESS and no file is provided in the form POST.

No segmentation fault occurs when I remove the APC_UPLOAD_PROGRESS hidden field.

Please refer to the Post Data below.

Reproduce code:
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Post Data (Note that a file field is provided, but it is blank):

Content-Type: multipart/form-data; boundary=---------------------------20600524916519 Content-Length: 1067 -----------------------------20600524916519 Content-Disposition: form-data; name="fileFolderId" A1C8C933933919359DB0048F3E976D90 -----------------------------20600524916519 Content-Disposition: form-data; name="fileContextId" B1C8C933933919359DB0048F3E976DC7 -----------------------------20600524916519 Content-Disposition: form-data; name="groupId" CC4917A4C2EE52BD414917A4219C0B3E -----------------------------20600524916519 Content-Disposition: form-data; name="name" File Title -----------------------------20600524916519 Content-Disposition: form-data; name="copyright" File Copyright -----------------------------20600524916519 Content-Disposition: form-data; name="APC_UPLOAD_PROGRESS" C4C0364EB09000016AD2130DBDD3C160 -----------------------------20600524916519 Content-Disposition: form-data; name="description" File Description -----------------------------20600524916519 Content-Disposition: form-data; name="file"; filename="" Content-Type: application/octet-stream -----------------------------20600524916519--

Expected result:
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No segmentation fault. Gracefully ignore blank file field.

Actual result:
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Apache Error Log:

[Thu Apr 28 14:32:45 2011] [notice] child pid 25128 exit signal Segmentation fault (11)

Web Browser:

Blank response and blank response headers.