base: avoid evaluating macro argument multiple times.

Previously, in the regex test helpers, we would evaluate the haystack
expression again to generate the error message, which leads to
nonsensical errors if the expression returns a different value on the
second call (e.g. functions like dlerror which return null on subsequent
calls).

Test: bionic-unit-tests with a failure
Test: treehugger
Change-Id: I2126cefeb45e26638194af8a82d0f2a9d7196edf

0 files changed, 0 insertions, 0 deletions