build: propagate includedir

meson.build

@@ -84,7 +84,13 @@ foreach dep : dep_list
     endforeach
     incdirs = ROOT_dep.get_variable(cmake: 'PACKAGE_INCLUDE_DIRS').split(';')
   else
-    continue # skip declared dependencies
+    name = dep.get_variable(internal: 'name', default_value: dep.name())
+    if name == 'rcdb'
+      incdirs = [ dep.get_variable(internal: 'includedir') ]
+    else
+      warning(f'Unknown dependency "@name@"')
+      continue
+    endif
   endif
 
   # append to `dep_*_dirs` arrays, uniquely

meson/get-env.py

@@ -1,8 +1,15 @@
 #!/usr/bin/env python3
 
-# meson forbids custom environment variables; this script allows for it,
-# but is only used as a last resort
-# details: https://github.com/mesonbuild/meson/issues/9
+# Meson forbids custom environment variables; however, our primary deployment
+# platform uses Environment Modules, which heavily relies on environment
+# variables. Assuming most of our users don't want to worry about this
+# constraint, this script grants Meson access to certain environment variables
+# from dependencies that need them.
+#
+# Build options are provided which take prioroty over such environment
+# variables; usage of this script should ONLY be a last resort.
+#
+# Details: https://github.com/mesonbuild/meson/issues/9
 
 from sys import argv, exit
 from os import environ

subprojects/rcdb/meson.build

@@ -2,27 +2,36 @@ project(
   'rcdb',
   'cpp',
   meson_version: '>=1.2',
+  version: 'iguana subproject'
 )
 
 use_rcdb = false
 rcdb_home = get_option('home')
-rcdb_headers = get_option('home') / 'cpp' / 'include'
+includedir = get_option('home') / 'cpp' / 'include'
 
 if get_option('home') != ''
   fs = import('fs')
-  if fs.is_dir(rcdb_headers)
+  if fs.is_dir(includedir)
     use_rcdb = true
   else
-    warning(f'RCDB include directory "@rcdb_headers@" does not exist; RCDB will not be used')
+    warning(f'RCDB include directory "@includedir@" does not exist; RCDB will not be used')
   endif
 else
   warning('RCDB not found; either use build option "rcdb:home" or set environment variable "$RCDB_HOME"')
 endif
 
 rcdb_dep = not use_rcdb ? dependency('', required: false) : declare_dependency(
-  version: get_option('home'), # could use `module info-loaded rcdb` on ifarm, but `get_option('home')` is platform independent
+  # RCDB lacks a public version number, use its prefix instead to at least
+  # inform the user which RCDB installation is used; alternatively, we could
+  # use `module info-loaded rcdb` on ifarm, but it's better to use a
+  # platform-independent approach
+  version: get_option('home'),
+  variables: {
+    'name': meson.project_name(),
+    'includedir': includedir,
+  },
   include_directories: include_directories(
-    rcdb_headers,
+    includedir,
     is_system: true, # suppress consumer warnings
   ),
 )