Re: [PATCH] C: fix reported range of invalid unary dereference.

[Jeff Law]

On 12/22/2015 10:26 AM, David Malcolm wrote:
Currently, trunk emits this for a bad unary * in C:
bad-dereference.c:10:10: error: invalid type argument of unary ‘*’ (have ‘int’)
    return *some_f.x;
           ^

The following patch fixes the reported location to highlight the
expression that was attempted to be dereferenced:

bad-dereference.c:10:10: error: invalid type argument of unary ‘*’ (have ‘int’)
    return *some_f.x;
           ^~~~~~~~~

Based on another example from:
   http://clang.llvm.org/diagnostics.html
albeit within the "Precision in Wording" example; I didn't change the
wording.

Successfully bootstrapped&regrtested on x86_64-pc-linux-gnu.
OK for trunk in stage 3?

gcc/c/ChangeLog:
        * c-parser.c (c_parser_unary_expression): For dereferences, build
        a combined location before calling build_indirect_ref, so that
        error reports cover the full range, manually updating the c_expr
        src_range.

gcc/testsuite/ChangeLog:
        * gcc.dg/bad-dereference.c: New test case.
I agree with Trevor here, move those curlys out to enclose the entire 
switch case.  It'll mean reformatting, but, meh...

Approved with that change.

jeff