[RFC PATCH] perf tools: Fix cross compile for ARM64

[John Garry]

Currently when cross compiling perf tool for ARM64 on my x86 machine I get
this error:
arch/arm64/util/sym-handling.c:9:10: fatal error: gelf.h: No such file or directory
 #include <gelf.h>

For the build, libelf is reported off:
Auto-detecting system features:
...
...                        libelf: [ OFF ]

Indeed, test-libelf is not built successfully:
more ./build/feature/test-libelf.make.output
test-libelf.c:2:10: fatal error: libelf.h: No such file or directory
 #include <libelf.h>
          ^~~~~~~~~~
compilation terminated.

I have no such problems natively compiling on ARM64, and I did not
previously have this issue for cross compiling. Fix by relocating
the gelf.h include.

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---

I marked this as RFC as I am suspicious that I have seen no other
reports, and whether fixing up the libelf.h include issue is the proper
approach.

diff --git a/tools/perf/arch/arm64/util/sym-handling.c b/tools/perf/arch/arm64/util/sym-handling.c
index 5df788985130..8dfa3e5229f1 100644
--- a/tools/perf/arch/arm64/util/sym-handling.c
+++ b/tools/perf/arch/arm64/util/sym-handling.c
@@ -6,9 +6,10 @@
 
 #include "symbol.h" // for the elf__needs_adjust_symbols() prototype
 #include <stdbool.h>
-#include <gelf.h>
 
 #ifdef HAVE_LIBELF_SUPPORT
+#include <gelf.h>
+
 bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
 {
 	return ehdr.e_type == ET_EXEC ||
-- 
2.17.1