Bug 195970
| Summary: | C++ compile error with casted char pointer passed as reference | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 4 | Reporter: | Hiroto Shibuya <shibuya> |
| Component: | gcc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED NOTABUG | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 4.0 | CC: | aoliva |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i686 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2006-12-13 10:44:45 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: | |||
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. GCC 3.2 was buggy in this regard. A cast to a non-reference type yields an rvalue, and binding rvalues to non-const references is forbidden. The referenced bug report is about an unrelated feature. |
Description of problem: Using gcc 3.4 on WS4, it generates error on C++ source which tries to cast unsigned char pointer to signed char pointer and then passes to a function as character pointer reference. This code used to compile fine on RedHat Linux 8.0 with gcc 3.2. Version-Release number of selected component (if applicable): $ gcc --version gcc (GCC) 3.4.5 20051201 (Red Hat 3.4.5-2) How reproducible: 100% Steps to Reproduce: 1. Save the following source as C++ source, castandref.cc ------8<------ begin source -------8<------- #include <stdio.h> /* This fails in WS4 with: astandref.cc: In function `int main()': castandref.cc:24: error: invalid initialization of non-const reference of type 'char*&' from a temporary of type 'char*' castandref.cc:16: error: in passing argument 1 of `void x(char*&)' due to the following bug http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16245 */ void x(char *&s) { s = "foobar"; } main() { unsigned char *s; x((char*)s); printf("%s\n", s); } ------8<------ end source -------8<------- 2. Compile with gcc Actual results: $ gcc castandref.cc castandref.cc: In function `int main()': castandref.cc:24: error: invalid initialization of non-const reference of type 'char*&' from a temporary of type 'char*' castandref.cc:16: error: in passing argument 1 of `void x(char*&)' Expected results: $ gcc castandref.cc $ ./a.out foobar Additional info: This seems to be a regression in gcc 3.4 described here. http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16245 which claim to have it fixed in gcc 4.0 but not in 3.4. This works fine in gcc 3.3 and lower.