Completion not working inside BOOST_TEST macro

Given the following code:

BOOST_AUTO_TEST_CASE(Test1)
{
  int foobar = 42;
  BOOST_CHECK_EQUAL(foobar, foobar);  // #1
  BOOST_TEST(foobar == foobar);       // #2
}

• On line #1, as soon as I type "fo", a completion popup appears for "foobar" (among dozens of other choices).
• On line #2, only built-in keywords such as "for" and "for range-based" are suggested.

This is with the latest 8.0.0 snapshot (May 18) and with clangd enabled.