diff mbox series

[2/2] Makefile: Remove -g from default CFLAGS

Message ID tencent_07F41222A743779181827FB2F0EAE7BECE08@qq.com
State New
Headers show
Series Enable Dead Code Elimination | expand

Commit Message

Kele Zhang Aug. 24, 2024, 8:19 a.m. UTC 
Remove `-g` from default CFLAGS as it should not be used in production
builds. Adjust optimization level to `-Og` when DEBUG is enabled.

Signed-off-by: Kele Zhang <1952088712@qq.com>
Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
---
 Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Bin Meng Aug. 28, 2024, 2:50 p.m. UTC | #1 
On Sat, Aug 24, 2024 at 4:22 PM Kele Zhang <1952088712@qq.com> wrote:
>
> Remove `-g` from default CFLAGS as it should not be used in production
> builds. Adjust optimization level to `-Og` when DEBUG is enabled.

The production build does not use ELF images to program onto the board
but the plain binary image instead. So `-g`should be fine. As for
`-Og` vs. `-O0` I prefer using `-O0` as `-Og` sometimes breaks
debugging.

>
> Signed-off-by: Kele Zhang <1952088712@qq.com>
> Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
> ---
>  Makefile | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 9abea9f..bcec588 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -346,9 +346,9 @@ GENFLAGS    +=      $(libsbiutils-genflags-y)
>  GENFLAGS       +=      $(platform-genflags-y)
>  GENFLAGS       +=      $(firmware-genflags-y)
>
> -CFLAGS         =       -g -Wall -Werror -ffreestanding -nostdlib -fno-stack-protector -fno-strict-aliasing -ffunction-sections -fdata-sections -Wl,--gc-sections
> +CFLAGS         =       -Wall -Werror -ffreestanding -nostdlib -fno-stack-protector -fno-strict-aliasing -ffunction-sections -fdata-sections -Wl,--gc-sections
>  ifneq ($(DEBUG),)
> -CFLAGS         +=      -O0 -Wl,--print-gc-sections
> +CFLAGS         +=      -Og -Wl,--print-gc-sections
>  else
>  CFLAGS         +=      -O2
>  endif

Regards,
Bin
Jessica Clarke Aug. 28, 2024, 3:01 p.m. UTC | #2 
On 28 Aug 2024, at 15:50, Bin Meng <bmeng.cn@gmail.com> wrote:
> 
> On Sat, Aug 24, 2024 at 4:22 PM Kele Zhang <1952088712@qq.com> wrote:
>> 
>> Remove `-g` from default CFLAGS as it should not be used in production
>> builds. Adjust optimization level to `-Og` when DEBUG is enabled.
> 
> The production build does not use ELF images to program onto the board
> but the plain binary image instead. So `-g`should be fine.

And even for boards that do, -g is the right thing to do. If you don’t
want debugging symbols, strip the binary, but it’s useful to default to
including them; distributions generally do exactly that, stripping the
installed binary but keeping the debug symbols around in a separate
.debug file.

Debug symbols also aren’t loaded into memory, they only exist on disk,
so the only cost is a bit of disk space.

Jess
diff mbox series

Patch

diff --git a/Makefile b/Makefile
index 9abea9f..bcec588 100644
--- a/Makefile
+++ b/Makefile
@@ -346,9 +346,9 @@  GENFLAGS	+=	$(libsbiutils-genflags-y)
 GENFLAGS	+=	$(platform-genflags-y)
 GENFLAGS	+=	$(firmware-genflags-y)
 
-CFLAGS		=	-g -Wall -Werror -ffreestanding -nostdlib -fno-stack-protector -fno-strict-aliasing -ffunction-sections -fdata-sections -Wl,--gc-sections
+CFLAGS		=	-Wall -Werror -ffreestanding -nostdlib -fno-stack-protector -fno-strict-aliasing -ffunction-sections -fdata-sections -Wl,--gc-sections
 ifneq ($(DEBUG),)
-CFLAGS		+=	-O0 -Wl,--print-gc-sections
+CFLAGS		+=	-Og -Wl,--print-gc-sections
 else
 CFLAGS		+=	-O2
 endif