From 0065df3a69e897e2863f5f8818fcd94492557fa7 Mon Sep 17 00:00:00 2001
From: Jade Abraham <jade.abraham@hpe.com>
Date: Thu, 26 Sep 2024 16:07:37 -0700
Subject: [PATCH] tighten warning for libs.private

Signed-off-by: Jade Abraham <jade.abraham@hpe.com>
---
 util/chplenv/third_party_utils.py | 34 +++++++++++++++++++++++++++----
 1 file changed, 30 insertions(+), 4 deletions(-)

diff --git a/util/chplenv/third_party_utils.py b/util/chplenv/third_party_utils.py
index 8006b3dfda47..0f0a2b332b60 100644
--- a/util/chplenv/third_party_utils.py
+++ b/util/chplenv/third_party_utils.py
@@ -128,6 +128,20 @@ def pkgconfig_get_system_compile_args(pkg):
     cflags = cflags_line.split()
     return ([ ], cflags)
 
+# helper function to determine if we need to warn about 'Requires'/'Requires.private'
+# these fields list other packages that are required to link with this package
+# however, this only matters if the required package is not listed in
+# 'Libs'/'Libs.private' already
+# see https://people.freedesktop.org/~dbn/pkg-config-guide.html
+def _pkgconfig_should_warn_for_requires(d, private=False):
+    libs = d['Libs' if not private else 'Libs.private'].split()
+    requires = d['Requires' if not private else 'Requires.private'].split()
+    for req in requires:
+        lib_name = '-l' + req
+        if lib_name not in libs:
+            return True
+    return False
+
 #
 # Return compiler arguments required to use a bundled library
 # based on a pkg-config .pc file.
@@ -154,8 +168,16 @@ def pkgconfig_get_bundled_compile_args(pkg, ucp='', pcfile=''):
         return ([ ], [ ])
 
     if 'Requires' in d and d['Requires']:
-        warning("Simple pkg-config parser does not handle Requires")
-        warning("in {0}".format(pcpath))
+        warn = False
+        if 'Libs' in d:
+            warn = _pkgconfig_should_warn_for_requires(d)
+        else:
+            # no Libs, so no way to check if the required package is already included
+            warn = True
+
+        if warn:
+            warning("Simple pkg-config parser does not handle Requires")
+            warning("in {0}".format(pcpath))
 
     cflags = [ ]
 
@@ -236,11 +258,15 @@ def pkgconfig_get_bundled_link_args(pkg, ucp='', pcfile='',
     if d == None:
         return ([ ], [ ])
 
-    if 'Requires' in d and d['Requires']:
+    if d.get('Requires') and _pkgconfig_should_warn_for_requires(d):
         warning("Simple pkg-config parser does not handle Requires")
         warning("in {0}".format(pcpath))
 
-    if static and 'Requires.private' in d and d['Requires.private']:
+    if (
+        static
+        and d.get("Requires.private")
+        and _pkgconfig_should_warn_for_requires(d, private=True)
+    ):
         warning("Simple pkg-config parser does not handle Requires.private")
         warning("in {0}".format(pcpath))