/usr/lib/pkgconfig/ACE.pc is in libace-dev 6.0.3+dfsg-0.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | prefix=/usr
exec_prefix=/usr
libdir=/usr/lib
includedir=/usr/include
Name: ACE
Description: ADAPTIVE Communication Environment
Version: 6.0.3
Libs: -L${libdir} -lACE -ldl -lrt
Cflags: -I${includedir}
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