Bug 1280272
| Summary: | possible use of uninitialized values (found by address sanitizer at build time) | ||||||
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| Product: | Red Hat Enterprise Linux 7 | Reporter: | David Jaša <djasa> | ||||
| Component: | spice | Assignee: | Default Assignee for SPICE Bugs <rh-spice-bugs> | ||||
| Status: | CLOSED NOTABUG | QA Contact: | SPICE QE bug list <spice-qe-bugs> | ||||
| Severity: | unspecified | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | 7.2 | CC: | cfergeau, fidencio, fziglio, uril | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2016-02-17 08:34:55 UTC | Type: | Bug | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Attachments: |
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(In reply to David Jaša from comment #0) > Created attachment 1092642 [details] > full build log (including less serious bugs - unused variables and results) > > Description of problem: > rebuild of spice-server with address sanitizer enabled yields these errors: > ---- > glz_encoder_dictionary.c: In function 'glz_dictionary_pre_encode': > glz_encoder_dictionary.c:512:30: warning: 'prev_seg_id' may be used > uninitialized in this function [-Wmaybe-uninitialized] > dict->window.segs[prev_seg_id].next = seg_id; Never happens. This part of the code is just triggered when row != 0 and prev_seg_id is set in the first loop when row == 0. > ^ > glz_encoder_dictionary.c:488:22: note: 'prev_seg_id' was declared here > uint32_t seg_id, prev_seg_id; > ^ > ---- > red_channel.c: In function 'red_channel_client_wait_pipe_item_sent': > red_channel.c:2382:84: warning: 'end_time' may be used uninitialized in this > function [-Wmaybe-uninitialized] > timeout == -1 ? -1 : > end_time - red_now()); > > ^ Never happens as well. Christophe has a fix and a really nice commit message about this false-positive: http://cgit.freedesktop.org/spice/spice/commit/?id=1b6ced7ddafd1bc6e490af091427327b05c96b3fg I agree with Fabiano these are false positives. That's http://cgit.freedesktop.org/spice/spice/commit/?id=1b6ced7ddafd1bc6e490af091427327b05c96b3f As comments these are false positive. |
Created attachment 1092642 [details] full build log (including less serious bugs - unused variables and results) Description of problem: rebuild of spice-server with address sanitizer enabled yields these errors: ---- glz_encoder_dictionary.c: In function 'glz_dictionary_pre_encode': glz_encoder_dictionary.c:512:30: warning: 'prev_seg_id' may be used uninitialized in this function [-Wmaybe-uninitialized] dict->window.segs[prev_seg_id].next = seg_id; ^ glz_encoder_dictionary.c:488:22: note: 'prev_seg_id' was declared here uint32_t seg_id, prev_seg_id; ^ ---- red_channel.c: In function 'red_channel_client_wait_pipe_item_sent': red_channel.c:2382:84: warning: 'end_time' may be used uninitialized in this function [-Wmaybe-uninitialized] timeout == -1 ? -1 : end_time - red_now()); ^ ---- Version-Release number of selected component (if applicable): spice-server-0.12.4-15.el7.x86_64 libasan-4.8.5-4.el7.x86_64 How reproducible: always Steps to Reproduce: 1. grab a spice-server srpm, add these lines to %build section of .spec, rebuild: # sanitizer, disable -debug pkg %global optflags %(echo %{optflags} | sed 's/ -g / -ggdb -fno-omit-frame-pointer -fsanitize=address /') %global __global_ldflags %(echo "%{__global_ldflags} -fsanitize=address -lasan") %global __strip /bin/true %global debug_package %{nil} 2. 3. Actual results: warnings from Description are emitted Expected results: bugs (if any) should be fixed, harmless warnings may deserver some explanation or suppression. Additional info: