r249131 - in /trunk/gcc/go/gofrontend: MERGE ex...

[ian@gcc.gnu.org]

Author: ian
Date: Mon Jun 12 17:51:52 2017
New Revision: 249131

URL: https://gcc.gnu.org/viewcvs?rev=249131&root=gcc&view=rev
Log:
    compiler: avoid orphaning Bexpressions when processing conversions
    
    The method Type_conversion_expression::do_get_backend was (in some
    circumstances) creating a Bexpression for the source expression of the
    conversion and then throwing it away before using it. Fix up this
    method to insure that the call to get_backend() on the source
    expression is only made when the result will be used.
    
    Reviewed-on: https://go-review.googlesource.com/45350

Modified:
    trunk/gcc/go/gofrontend/MERGE
    trunk/gcc/go/gofrontend/expressions.cc