zig cc --sysroot=... does not work as expected for #includes #19638

❯ echo "#include <test.h>" > test.c
❯ mkdir -p sys/usr/include
❯ touch sys/usr/include/test.h
❯ gcc --sysroot=$PWD/sys test.c -shared
❯ clang --sysroot=$PWD/sys test.c -shared
/usr/bin/ld: cannot find crti.o: No such file or directory
/usr/bin/ld: cannot find libgcc_s.so.1: No such file or directory
clang: error: linker command failed with exit code 1 (use -v to see invocation)
❯ zig cc --sysroot=$PWD/sys test.c -shared
test.c:1:10: fatal error: 'test.h' file not found
#include <test.h>
         ^~~~~~~~
1 error generated.

❯ gcc --sysroot=$PWD/sys -E -Wp,-v - < /dev/null
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/usr/local/include"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/13/include-fixed/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/13/include-fixed"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/13/../../../../x86_64-linux-gnu/include"
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/usr/include/x86_64-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/x86_64-linux-gnu/13/include
 /home/alexrp/Source/tests/sys/usr/include
End of search list.
# 0 "<stdin>"
# 0 "<built-in>"
# 0 "<command-line>"
# 1 "<stdin>"
❯ clang --sysroot=$PWD/sys -E -Wp,-v - < /dev/null
clang -cc1 version 16.0.6 based upon LLVM 16.0.6 default target x86_64-pc-linux-gnu
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/usr/local/include"
ignoring nonexistent directory "/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../x86_64-linux-gnu/include"
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/llvm-16/lib/clang/16/include
 /home/alexrp/Source/tests/sys/usr/include
End of search list.
# 1 "<stdin>"
# 1 "<built-in>" 1
# 1 "<built-in>" 3
# 374 "<built-in>" 3
# 1 "<command line>" 1
# 1 "<built-in>" 2
# 1 "<stdin>" 2
❯ zig cc --sysroot=$PWD/sys -E -Wp,-v - < /dev/null
clang -cc1 version 16.0.6 based upon LLVM 16.0.6 default target x86_64-linux-musl
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/usr/local/include"
ignoring nonexistent directory "/usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../x86_64-linux-gnu/include"
ignoring nonexistent directory "/home/alexrp/Source/tests/sys/include"
ignoring nonexistent directory "/opt/lib/clang/16/include"
#include "..." search starts here:
#include <...> search starts here:
 /home/alexrp/Source/tests/sys/usr/include
End of search list.
# 1 "<stdin>"
# 1 "<built-in>" 1
# 1 "<built-in>" 3
# 375 "<built-in>" 3
# 1 "<command line>" 1
# 1 "<built-in>" 2
# 1 "<stdin>" 2