From 436a257c50de2b885a6483af3c708c289e7d986f Mon Sep 17 00:00:00 2001
From: Mat Cross <mathewc@nag.co.uk>
Date: Sun, 22 Aug 2021 10:21:16 +0100
Subject: [PATCH] Comments on nagfor options setup.

---
 mesonbuild/compilers/fortran.py | 1 +
 mesonbuild/linkers/linkers.py   | 9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/mesonbuild/compilers/fortran.py b/mesonbuild/compilers/fortran.py
index 1a430a7ae..07580114e 100644
--- a/mesonbuild/compilers/fortran.py
+++ b/mesonbuild/compilers/fortran.py
@@ -494,6 +494,7 @@ class NAGFortranCompiler(FortranCompiler):
                                  is_cross, info, exe_wrapper, linker=linker,
                                  full_version=full_version)
         self.id = 'nagfor'
+        # Warnings are on by default; -w disables (by category):
         self.warn_args = {
             '0': ['-w=all'],
             '1': [],
diff --git a/mesonbuild/linkers/linkers.py b/mesonbuild/linkers/linkers.py
index 58e432400..7523a8141 100644
--- a/mesonbuild/linkers/linkers.py
+++ b/mesonbuild/linkers/linkers.py
@@ -1047,7 +1047,14 @@ class QualcommLLVMDynamicLinker(LLVMDynamicLinker):
 
 class NAGDynamicLinker(PosixDynamicLinkerMixin, DynamicLinker):
 
-    """NAG Fortran linker, ld via gcc indirection."""
+    """NAG Fortran linker, ld via gcc indirection.
+
+    Using nagfor -Wl,foo passes option foo to a backend gcc invocation.
+    (This linking gathers the correct objects needed from the nagfor runtime
+    system.)
+    To pass gcc -Wl,foo options (i.e., to ld) one must apply indirection
+    again: nagfor -Wl,-Wl,,foo
+    """
 
     id = 'nag'