objtool: Validate disassembler headers in libopcodes probegrafted

commit 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
tested for libopcodes availability by linking a test snippet with a forward
declaration of disassemble_init_for_target().

However, testing symbol linkage with an extern declaration only verifies
the presence of the library (.so/.a) and bypasses checking for development
headers (binutils-dev). On systems where libopcodes is present without
development headers installed, the probe succeeds, enabling BUILD_DISAS.
Subsequent compilation of objtool then fails:

  fatal error: 'bfd.h' file not found
    113 | #include <bfd.h>

Additionally, the probe invokes $(HOSTCC) without $(HOSTCFLAGS), ignoring
any sysroot or include flags specified for the host compiler.

Fix this by including <bfd.h> and <dis-asm.h> directly in the test snippet,
passing $(HOSTCFLAGS) so host compiler options are respected, and defining
PACKAGE="objtool" to satisfy the configuration check in <bfd.h>.

Fixes: 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
Fixes: 436326bc525d ("objtool: fix build failure due to missing libopcodes check")
Reported-by: Alice Ryhl <aliceryhl@google.com>
Assisted-by: Antigravity:Gemini-Next
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>
Link: https://patch.msgid.link/20260904150710.2997558-1-umendez@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/clocksource/timer-versatile.c b/drivers/clocksource/timer-versatile.c
new file mode 100644
index 000000000..f5d017b31
--- /dev/null
+++ b/drivers/clocksource/timer-versatile.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Copyright (C) 2014 ARM Limited
+ */
+
+#include <linux/clocksource.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#define SYS_24MHZ 0x05c
+
+static void __iomem *versatile_sys_24mhz;
+
+static u64 notrace versatile_sys_24mhz_read(void)
+{
+	return readl(versatile_sys_24mhz);
+}
+
+static int __init versatile_sched_clock_init(struct device_node *node)
+{
+	void __iomem *base = of_iomap(node, 0);
+
+	of_node_clear_flag(node, OF_POPULATED);
+
+	if (!base)
+		return -ENXIO;
+
+	versatile_sys_24mhz = base + SYS_24MHZ;
+
+	sched_clock_register(versatile_sys_24mhz_read, 32, 24000000);
+
+	return 0;
+}
+TIMER_OF_DECLARE(vexpress, "arm,vexpress-sysreg",
+		       versatile_sched_clock_init);
+TIMER_OF_DECLARE(versatile, "arm,versatile-sysreg",
+		       versatile_sched_clock_init);