Bug 17853
| Summary: | Compiler warnings | ||
|---|---|---|---|
| Product: | [Retired] Red Hat Linux | Reporter: | Jimmy Timofte <jimmyt_104> |
| Component: | gcc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED NOTABUG | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 7.0 | ||
| 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: | 2000-09-26 09:59:22 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: | |||
The warnings are appropriate here, there is no need to put ## between ~ and identificator or between identificator and scope (::). The preprocessor really cannot paste the two tokens together, previous preprocessors silently ignored this. Either remove all ## from your examples (none of them are needed), all compile with -Wno-paste to avoid emiting those warnings. You program is wrong. The C++ standard says at 16.3.3/1: | A ## preprocessing token shall not occur at the beginning or at the end of a replacement list for | either form of macro definition. It's better to write `~NAME' and `NAME::NAME' directly. Thank you very much. Anyway, this is not really my program. These warnings appeared when compiling mysql++ v1.7.5 module. Thank you for your quick response. |
The gcc compiler gives some warning messages when trying to compile the following examples: /*example1.c*/ #define CLASS(NAME) \ class NAME \ { \ public: \ NAME() {}; \ ~##NAME() {}; \ } \ CLASS(Test); void main() {} /* example2.c */ #define CLASS(NAME) \ class NAME \ { \ public: \ NAME(); \ }; \ \ NAME##::##NAME() {}; CLASS(Test) void main() {} Here is the output for the compiling of example1.c: [jimmy@chopin test]$ g++ example1.c example1.c:7:5: warning: nothing can be pasted after this token Here is the output for the compiling of example2.c: [jimmy@chopin test]$ g++ example2.c example2.c:9:7: warning: nothing can be pasted after this token example2.c:11:11: warning: pasting would not give a valid preprocessing token The examples were compiled using g++ version 2.96: [jimmy@chopin test]$ g++ --version 2.96 That's all