pkgconfig: Improve and document generator behaviour

- Add libraries from InternalDependency.libraries
- Deprecate association of libraries from the "libraries" keyword
argument to the generated pkg-config file.

1 files changed, 34 insertions, 0 deletions

diff --git a/docs/markdown/snippets/pkgconfig_break.md b/docs/markdown/snippets/pkgconfig_break.md
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+## Deprecation warning in pkg-config generator
+
+All libraries passed to the `libraries` keyword argument of the `generate()`
+method used to be associated with that generated pkg-config file. That means
+that any subsequent call to `generate()` where those libraries appear would add
+the filebase of the `generate()` that first contained them into `Requires:` or
+`Requires.private:` field instead of adding an `-l` to `Libs:` or `Libs.private:`.
+
+This behaviour is now deprecated. The library that should be associated with
+the generated pkg-config file should be passed as first positional argument
+instead of in the `libraries` keyword argument. The previous behaviour is
+maintained but prints a deprecation warning and support for this will be removed
+in a future Meson release. If you can not create the needed pkg-config file
+without this warning, please file an issue with as much details as possible
+about the situation.
+
+For example this sample will write `Requires: liba` into `libb.pc` but print a
+deprecation warning:
+```meson
+liba = library(...)
+pkg.generate(libraries : liba)
+
+libb = library(...)
+pkg.generate(libraries : [liba, libb])
+```
+
+It can be fixed by passing `liba` as first positional argument::
+```meson
+liba = library(...)
+pkg.generate(liba)
+
+libb = library(...)
+pkg.generate(libb, libraries : [liba])
+```