objtool: fix build failure due to missing libopcodes check

Commit 59953303827e ("objtool: Disassemble code with libopcodes instead
of running objdump") added support for using libopcodes for disassembly.
However, the feature detection checks for libbfd availability but then
unconditionally links against libopcodes:

  ifeq ($(feature-libbfd),1)
      OBJTOOL_LDFLAGS += -lopcodes
  endif

This causes build failures in environments where libbfd is installed but
libopcodes is not, since the test-libbfd.c feature test only links
against -lbfd and -ldl, not -lopcodes:

  /usr/bin/ld: cannot find -lopcodes: No such file or directory
  collect2: error: ld returned 1 exit status
  make[4]: *** [Makefile:109: objtool] Error 1

Additionally, the shared feature framework uses $(CC) which is the
cross-compiler in cross-compilation builds. Since objtool is a host tool
that links with $(HOSTCC) against host libraries, the feature detection
can falsely report libopcodes as available when the cross-compiler's
sysroot has it but the host system doesn't.

Fix this by replacing the feature framework check with a direct inline
test that uses $(HOSTCC) to compile and link a test program against
libopcodes, similar to how xxhash availability is detected.

Fixes: 59953303827e ("objtool: Disassemble code with libopcodes instead of running objdump")
Assisted-by: claude-opus-4-5-20251101
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251223120357.2492008-1-sashal@kernel.org

0 files changed, 0 insertions, 0 deletions