perf build: Add Wextra for C++ compilation

Commit d58ac0bf8d1e ("perf build: Add clang and llvm compile and
linking support") added -Wall and -Wno-strict-aliasing for CXXFLAGS,
but not -Wextra. -Wno-strict-aliasing is no longer necessary, adding
-Wextra for CXXFLAGS requires adding -Wno-unused-parameter clang.cpp
and clang-test.cpp for LIBCLANGLLVM=1 to build.

Signed-off-by: Ian Rogers <[email protected]>
Acked-by: James Clark <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Eduard Zingerman <[email protected]>
Cc: Gaosheng Cui <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Tom Rix <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/tools/perf/util/c++/Build b/tools/perf/util/c++/Build
index 613ecfd76527..8610d032ac19 100644
--- a/tools/perf/util/c++/Build
+++ b/tools/perf/util/c++/Build
@@ -1,2 +1,5 @@
 perf-$(CONFIG_CLANGLLVM) += clang.o
 perf-$(CONFIG_CLANGLLVM) += clang-test.o
+
+CXXFLAGS_clang.o += -Wno-unused-parameter
+CXXFLAGS_clang-test.o += -Wno-unused-parameter