Malcolm: Usability improvements in GCC 9

David Malcolm writes
about improved diagnostics and more in the GCC 9 release.
'Speaking of annotations, this example shows another new GCC 9
feature: diagnostics can label regions of the source code to show pertinent
information. Here, what’s most important are the types of the left-hand and
right-hand sides of the '+' operator, so GCC highlights them inline. Notice
how the diagnostic also uses color to distinguish the two operands from
each other and the operator.'