Mike Stump <mikest...@comcast.net> writes: > On Dec 14, 2015, at 2:40 AM, Rainer Orth <r...@cebitec.uni-bielefeld.de> > wrote: >> As described in PR PR target/67973, newer assemblers on Mac OS X, which >> are based on LLVM instead of gas, don't support .stab* directives any >> longer. The following patch detects this situation and tries to fall >> back to the older gas-based as if it is still accessible via as -Q. >> >> Tested on x86_64-apple-darwin15.2.0 and as expected the -gstabs* tests >> now pass. >> >> However, I'm not really comfortable with this solution. > > When I proposed automagically adding -Q, it sounded like a good idea. :-( > > Yeah, hard to disagree with your intuition. If a future assembler had or > added stabs that had or added all these features, it would come first on > the path, and it all work just work out nicely with just a configure check > to disable stabs if it didn’t work. That simple check should be reliable > and work well.
Right: I'm effectively keeping just the first configure test for .stabs support in the assembler to enable or disable DBX_DEBUG/DBX_DEBUGGING_INFO. I'll post it later since ... >> Initially, I >> forgot to wrap the -Q option to as in %{gstabs*:...}, which lead to a >> bootstrap failure: the gas- and LLVM-based assemblers differ in a >> number of other ways > > Yeah, having the feature set be a dynamic property when our software > decides on static basis is bound to hurt. Seem that the most likely patch > would be to just turn off stabs in a way that the test suite disables the > tests by itself, or to just quite the tests suite. ... testing revealed another instance of static assumptions which hurts us now: while support for -gstabs* is checked for dynamically in lib/gcc-dg.exp and lib/gfortran-dg.exp for the debug.exp tests, there are a couple of testcases that use -gstabs* unconditionally, but have a hardcoded list of targets that support those options. I'll introduce a new effective-target keyword (simply checking if -gstabs is accepted should be enough) to also perform this test dynamically and repost once it's tested. Rainer -- ----------------------------------------------------------------------------- Rainer Orth, Center for Biotechnology, Bielefeld University