Created attachment 924336 [details] diagnostics color test code : #include <cstring> int main() { int i=1; int *j = i; return 0; } in shell $g++ test.cxx will have a diagnostics color output. but $g++ -c test.cxx and $g++ -c -fdiagnostics-color=auto test.cxx the output is black. I just use $g++ -c -fdiagnostics-color=always test.cxx. so -c and default diagnostics-color not compatible
when i remove ccache,the output have color.
Don't use ccache then, this is something beyond control of gcc.
ccache 3.2 (entering rawhide soon) seems to have this partially fixed, these give colorized output with it: g++ test.cxx g++ -c -fdiagnostics-color=auto test.cxx ...but this still doesn't: g++ -c test.cxx
Don't you need to set GCC_COLORS (or pass -fdiagnostics-color) to get color diagnostics from GCC in Fedora? /ccache upstream maintainer, not running Fedora
Fedora has the same default as upstream trunk, i.e. even if GCC_COLORS env var is not defined, colors are output if stderr is a tty and TERM is not dumb. I.e. as if trunk has been configured with the default --with-diagnostics-color=auto. Upstream 4.9 on the other side defaults to trunk's --with-diagnostics-color=auto-if-env. See https://gcc.gnu.org/gcc-5/changes.html for more details.
This message is a reminder that Fedora 20 is nearing its end of life. Approximately 4 (four) weeks from now Fedora will stop maintaining and issuing updates for Fedora 20. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as EOL if it remains open with a Fedora 'version' of '20'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version. Thank you for reporting this issue and we are sorry that we were not able to fix it before Fedora 20 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora, you are encouraged change the 'version' to a later Fedora version prior this bug is closed as described in the policy above. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete.
From a ccache point of view, I don't see any good solution for this issue. The problem is that ccache needs to pass -fdiagnostics-color to the preprocessor to get colored output and that is currently done if GCC_COLORS is set. ccache can't just pass -fdiagnostics-color unconditionally since it doesn't know whether the compiler is new enough to support it. Any ideas?
Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.