Add a testcase for PR ld/22751

Since dummy.o must be placed before

-Wl,--whole-archive tmpdir/pr22751.a -Wl,--no-whole-archive

to trigger the bug, this patch adds an optional trailing ld options to
run_ld_link_exec_tests.

	PR ld/22751
	* testsuite/config/default.exp (INT128_CFLAGS): New.
	* testsuite/ld-plugin/lto.exp (INT128_CFLAGS): New.
	Run ld/22751 tests.
	* testsuite/ld-plugin/pr22751.c: New file.
	* testsuite/lib/ld-lib.exp (run_ld_link_exec_tests): Add
	ld trailing options.

1 files changed, 37 insertions, 0 deletions

diff --git a/ld/testsuite/config/default.exp b/ld/testsuite/config/default.exp
index 29c020f..fe3bd32 100644
--- a/ld/testsuite/config/default.exp
+++ b/ld/testsuite/config/default.exp
@@ -376,3 +376,40 @@ if { ![info exists GNU2_CFLAGS] } then {
 	set GNU2_CFLAGS ""
     }
 }
+
+# Set INT128_CFLAGS to "-DHAS_INT128" if target compiler supports __int128.
+
+if { ![info exists INT128_CFLAGS] } then {
+    if { [which $CC] != 0 } {
+	# Check if gcc supports __int128.
+	set flags ""
+	if [board_info [target_info name] exists cflags] {
+	    append flags " [board_info [target_info name] cflags]"
+	}
+	if [board_info [target_info name] exists ldflags] {
+	    append flags " [board_info [target_info name] ldflags]"
+	}
+
+	set basename "tmpdir/int128[pid]"
+	set src ${basename}.c
+	set output ${basename}.o
+	set f [open $src "w"]
+	puts $f "__int128 a = 42;"
+	close $f
+	if [is_remote host] {
+	    set src [remote_download host $src]
+	}
+	set int128_available [run_host_cmd_yesno "$CC" "$flags -c $src -o $output"]
+	remote_file host delete $src
+	remote_file host delete $output
+	file delete $src
+
+	if { $int128_available == 1 } then {
+	    set INT128_CFLAGS "-DHAS_INT128"
+	} else {
+	    set INT128_CFLAGS ""
+	}
+    } else {
+	set INT128_CFLAGS ""
+    }
+}