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Message-ID: <bd06ac8f-f3be-cd46-7dd7-86db7e7b7c63@arm.com>
Date:   Fri, 28 Jul 2023 09:56:43 +0100
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Subject: Re: [PATCH v1 2/6] perf build: Don't always set -funwind-tables and
 -ggdb3
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To:     Ian Rogers <irogers@google.com>
References: <20230728064917.767761-1-irogers@google.com>
 <20230728064917.767761-3-irogers@google.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>,
        Kan Liang <kan.liang@linux.intel.com>,
        Eduard Zingerman <eddyz87@gmail.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Gaosheng Cui <cuigaosheng1@huawei.com>,
        Rob Herring <robh@kernel.org>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org, llvm@lists.linux.dev
From:   James Clark <james.clark@arm.com>
In-Reply-To: <20230728064917.767761-3-irogers@google.com>
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Precedence: bulk


On 28/07/2023 07:49, Ian Rogers wrote:
> Commit 6a40cd90f5de ("perf tools: Add libunwind dependency for DWARF
> CFI unwinding") added libunwind support but also -funwind-tables and
> -ggdb3 to the standard build. These build flags aren't necessary so
> remove, set -g when DEBUG is enabled for the build.
> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/Makefile.config | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> index a9cfe83638a9..14709a6bd622 100644
> --- a/tools/perf/Makefile.config
> +++ b/tools/perf/Makefile.config
> @@ -246,6 +246,9 @@ ifeq ($(CC_NO_CLANG), 0)
>  else
>    CORE_CFLAGS += -O6
>  endif
> +else
> +  CORE_CFLAGS += -g
> +  CXXFLAGS += -g
>  endif
>  
>  ifdef PARSER_DEBUG
> @@ -324,8 +327,6 @@ FEATURE_CHECK_LDFLAGS-disassembler-four-args = -lbfd -lopcodes -ldl
>  FEATURE_CHECK_LDFLAGS-disassembler-init-styled = -lbfd -lopcodes -ldl
>  
>  CORE_CFLAGS += -fno-omit-frame-pointer
> -CORE_CFLAGS += -ggdb3
> -CORE_CFLAGS += -funwind-tables
>  CORE_CFLAGS += -Wall
>  CORE_CFLAGS += -Wextra
>  CORE_CFLAGS += -std=gnu11
> @@ -333,8 +334,6 @@ CORE_CFLAGS += -std=gnu11
>  CXXFLAGS += -std=gnu++14 -fno-exceptions -fno-rtti
>  CXXFLAGS += -Wall
>  CXXFLAGS += -fno-omit-frame-pointer
> -CXXFLAGS += -ggdb3
> -CXXFLAGS += -funwind-tables
>  CXXFLAGS += -Wno-strict-aliasing
>  
>  HOSTCFLAGS += -Wall

Acked-by: James Clark <james.clark@arm.com>