pkg-config --exists does not check Requires: any longer

[Tollef Fog Heen]

]] "Peter O'Gorman" 

| We recently updated our pkg-config from 0.23 to 0.25 and find that
| PKG_CHECK_MODULES no longer complains if a dir is missing, and the
| _CFLAGS and _LIBS for the module end up empty.

This is a bug.

| For example (having set PKG_CONFIG_PATH, but not including the path to
| libiconv.pc):
| % pkg-config --exists libxml-2.0
| % echo $?
| 0

This looks somewhat odd, but I'd need to check the bug reports to figure
out how it's wrong.

| We have worked around this, patch below, but wonder if the above
| behaviour is intentional?

The m4 macro should certainly not be broken and I suspect the --exists
handling is broken too.

-- 
Tollef Fog Heen
UNIX is user friendly, it's just picky about who its friends are