Nathan Sidwell <nat...@acm.org> writes: Hi Nathan, thanks so much for looking at this!
> On 02/22/16 12:03, Aaron Conole wrote: >> The previous gcov behavior was to always output errors on the stderr channel. >> This is fine for most uses, but some programs will require stderr to be >> silent for certain tests. This change allows configuring the gcov output by >> an environment variable which will be used to open the appropriate file. > > Why is the invoker unable to direct fd2 before execing gcov? I want to make sure I understand your question. You are asking why something like: ` ./program_executed 2>/path/to/file `` is not preferred? If this is the question, the problem is program errors will be intermingled with gcov error messages. Let's suppose that I've got a unit test program (since that's what I have as specifically happening). I expect certain tests from that program to spit out errors on stderr. So, I filter out that text in stderr, so normal case stderr results will be clear. Now, I build with gcov enabled. In this case, gcov writes 'profiling:...' to stderr. Now, the test fails, even though nothing changed apart from using gcov. Sometimes this is a real user error (clean .gcda and .gcno files, do clean build and then rerun), but other times, for instance if I use openvswitch's 'make check', there is no rebuild which happens, but gcov has merge mismatch errors anyway. I want to not squelch those errors, but I don't want them intermingled with the program's error output. I hope I explained myself and answered your question. Please let me know if I didn't. Thanks again, -Aaron > nathan
