[Bug bootstrap/56364] New: autoconf compiler switches are also used to link and they can fail (-fno-rtti -fno-exceptions Solaris cc/ld)

["jay.krell at cornell dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56364

             Bug #: 56364
           Summary: autoconf compiler switches are also used to link and
                    they can fail (-fno-rtti -fno-exceptions Solaris
                    cc/ld)
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jay.krell@cornell.edu


Solaris cc and CC accept with warning -fno-rtti and -fno-exceptions.
But they are passed on to the Solaris linker, and it rejects them with an
error.


In 4.7.2/gcc/configure, -fno-rtti -fno-exceptions are tested
only for compilation, but if that works, they are also used for linking (in
gcc/Makefile).


Suggested fixes, one of:


1) just never use -fno-rtti -fno-exceptions
   Not a bad idea I think. Is there really noticable overhead these days?
   Less autoconf, more portability, is good.


2) only use -fno-rtti -fno-exceptions if using gcc 
   pretty easy and safe and no-change for most folks 


3) only compile with -fno-rtti -fno-exceptions, but don't link with them


4) test -fno-rtti -fno-exceptions with compiling and linking use
  them where they work and not where they don't; i.e. w/ and w/o "-c" 


 - Jay