gobject-introspection: Configure failure on Big Sur 11.1 and Xcode 12.3

[mf2k (Frank Schima)]

gobject-introspection fails to configure with Big Sur 11.1 and Xcode 12.3 and the latest command line tools installed. It seems to want SDK 11.0 but it should be using SDK 11.1.

Is this a base issue?

:debug:extract SDKROOT='/Library/Developer/CommandLineTools/SDKs/MacOSX11.0.sdk'
...
:info:configure     /usr/bin/clang -pipe -Os -DNDEBUG -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX11.0.sdk  -arch x86_64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX11.0.sdk -mmacosx-version-min=11.0 -Wl,-search_paths_first -Wl,-headerpad_max_install_names -Wl,-headerpad_max_install_names -liconv -Wl,-syslibroot,/Library/Developer/CommandLineTools/SDKs/MacOSX11.0.sdk  CMakeFiles/cmTC_b03d4.dir/testCCompiler.c.o -o cmTC_b03d4 
:info:configure     ld: library not found for -lSystem
:info:configure     clang: error: linker command failed with exit code 1 (use -v to see invocation)
:info:configure     make[1]: *** [cmTC_b03d4] Error 1
:info:configure     make: *** [cmTC_b03d4/fast] Error 2

Here is what I have installed:

$ ls -l /Library/Developer/CommandLineTools/SDKs/
total 0
lrwxr-xr-x  1 root  wheel   14 Dec 14 13:41 MacOSX.sdk -> MacOSX11.1.sdk
drwxr-xr-x  7 root  wheel  224 Nov 12  2019 MacOSX10.14.sdk
drwxr-xr-x  8 root  wheel  256 Dec 14 13:41 MacOSX10.15.sdk
drwxr-xr-x  4 root  wheel  128 Dec 14 13:41 MacOSX11.0.sdk
drwxr-xr-x  7 root  wheel  224 Nov 30 05:33 MacOSX11.1.sdk

and

$ xcrun --show-sdk-path
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk

$ xcrun --show-sdk-version 
11.1