Subject: meson: Fix support for empty darwin sysroot

From: Peter Eisentraut <[email-masked]>
Date: Wed, 22 Mar 2023 08:34:00 +0100

The -isysroot options should only be added if the sysroot resolved to a 
nonempty string.  This matches the behavior in src/template/darwin (also 
documented in installation.sgml).
From 6012fe86627db134aa48ed55f5d9086931b399e0 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <[email-masked]>
Date: Wed, 22 Mar 2023 08:05:45 +0100
Subject: [PATCH] meson: Fix support for empty darwin sysroot

The -isysroot options should only be added if the sysroot resolved to
a nonempty string.  This matches the behavior in src/template/darwin
(also documented in installation.sgml).
---
 meson.build | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/meson.build b/meson.build
index 7f76a101ec..9fb7fda539 100644
--- a/meson.build
+++ b/meson.build
@@ -233,8 +233,10 @@ elif host_system == 'darwin'
   sysroot_args = [files('src/tools/darwin_sysroot'), get_option('darwin_sysroot')]
   pg_sysroot = run_command(sysroot_args, check:true).stdout().strip()
   message('darwin sysroot: @0@'.format(pg_sysroot))
-  cflags += ['-isysroot', pg_sysroot]
-  ldflags += ['-isysroot', pg_sysroot]
+  if pg_sysroot != ''
+    cflags += ['-isysroot', pg_sysroot]
+    ldflags += ['-isysroot', pg_sysroot]
+  endif
   # meson defaults to -Wl,-undefined,dynamic_lookup for modules, which we
   # don't want because a) it's different from what we do for autoconf, b) it
   # causes warnings starting in macOS Ventura
-- 
2.40.0