tools: allow use of NM env variable

Bug: https://bugs.gentoo.org/968162
Signed-off-by: Alfred Wingate <parona@protonmail.com>

libgimp/meson.build

@@ -628,6 +628,8 @@ else
 endif
 
 if not platform_osx and host_cpu_family != 'x86'
+  nm = find_program('nm', required: false)
+
   # Verify .def files for Windows linking.
   # We check this on non-Windows platform (Debian) on CI, and on Windows itself.
   custom_target('check-def-files',
@@ -653,6 +655,7 @@ if not platform_osx and host_cpu_family != 'x86'
       libgimpthumb,
       libgimpwidgets
     ],
+    env: nm.found() ? { 'NM': nm.full_path() } : {},
     output: [ 'check-def-files', ],
     command: [
       python, meson.project_source_root() / 'tools' / 'defcheck.py', meson.project_source_root(),

tools/defcheck.py

@@ -31,7 +31,7 @@ Needs the tool "nm", "objdump" or "dumpbin" to work
 
 import os, sys, subprocess, shutil
 
-from os import path
+from os import getenv, path
 
 def_files = (
    "libgimpbase/gimpbase.def",
@@ -55,7 +55,7 @@ if len(sys.argv) > 1:
       sys.exit (-1)
 
 libextension   = ".so"
-command        = "nm --defined-only --extern-only "
+command        = getenv("NM", default="nm") + " --defined-only --extern-only "
 libprefix      = "lib"
 platform_linux = True