Bug 33690
| Summary: | Pointer comparisons skipped in execution | ||
|---|---|---|---|
| Product: | [Retired] Red Hat Linux | Reporter: | Need Real Name <swade> |
| Component: | gcc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED RAWHIDE | QA Contact: | David Lawrence <dkl> |
| Severity: | high | Docs Contact: | |
| Priority: | medium | ||
| Version: | 7.0 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i386 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2001-03-30 07:52:27 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Verified both in gcc-2.96-80 and gcc-3_0-branch plus gcc-3_1-branch. Debugging... Fixed, the fix will appear in 2.96-81. I've mailed it to gcc-patches too (but gcc.gnu.org is dead ATM, so I cannot provide URL to the patch). FYI, the patch is at http://gcc.gnu.org/ml/gcc-patches/2001-03/msg01977.html |
From Bugzilla Helper: User-Agent: Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 4.0; NAI IE4 Build 4) Given this code sample: #define HKEY_CLASSES_ROOT ((void *)0x80000000) #define HKEY_DYN_DATA ((void *)0x80000005) void *hKey = ((void *)0x80000001); if (hKey>=HKEY_CLASSES_ROOT && hKey<=HKEY_DYN_DATA) printf("In range\n"); else printf("Out of range\n"); printf("Low: %u High: %u hKey: %u\n", (unsigned long)H_KEY_CLASSES_ROOT, (unsigned long)H_KEY_DYN_DATA, (unsigned long)hKey); The comparison is never even performed. It's skipped over in gdb and the "else" automatically executes without performing the comparison. This, however, works without a problem: if ((unsigned long)hKey>=(unsigned long)HKEY_CLASSES_ROOT && (unsigned long)hKey<=(unsigned long)HKEY_DYN_DATA) printf("In range\n"); Reproducible: Always Steps to Reproduce: 1. Enter above code sample. 2. Compile (i.e. gcc sample.c -o sample -g -lc) 3. Execute sample. Actual Results: A comparison that should have resulted in true, was skipped in execution and assumed to have a false result. Expected Results: The comparison would be performed and validly determine true or false. gcc-2.96-69 kernel-2.2.16-22 gdb-5.0-7