[PATCH 0/3] HOSTCFLAGS and HOSTLDFLAGS from the environment

[PATCH 0/3] HOSTCFLAGS and HOSTLDFLAGS from the environment

[Laura Abbott]

Hi,

Someone noted that scripts/tools userspace binaries packaged as part of
the Fedora kernel were not picking up the recommended compiler flags
(https://src.fedoraproject.org/rpms/redhat-rpm-config/blob/master/f/buildflags.md)
This series lets the host ld and C flags be set on the command line
similar to the kernel flags:

make AFLAGS_HOSTCFLAGS="%{build_cflags}" AFLAGS_HOSTLDFLAGS="%{build_ldflags}"

There's one more annoying case I didn't quite figure out with
tools/objtool/fixdep since that's linked with ld directly but this
covers the initial set of reports.

Thanks,
Laura

Laura Abbott (3):
  kbuild: Support HOSTLDFLAGS
  objtool: Support HOSTCFLAGS and HOSTLDFLAGS
  kbuild: Allow passing additional HOSTCFLAGS and HOSTLDFLAGS

 Documentation/kbuild/kbuild.txt | 9 +++++++++
 Makefile                        | 3 +++
 scripts/Makefile.host           | 6 +++---
 tools/build/Makefile.build      | 2 +-
 tools/objtool/Makefile          | 5 +++--
 5 files changed, 19 insertions(+), 6 deletions(-)

-- 
2.16.2

[PATCH 1/3] kbuild: Support HOSTLDFLAGS

[Laura Abbott]

In addition to HOSTCFLAGS, there's HOSTLDFLAGS. Ensure these get passed to
calls to build host binaries.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
 scripts/Makefile.host      | 6 +++---
 tools/build/Makefile.build | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/scripts/Makefile.host b/scripts/Makefile.host
index e6dc6ae2d7c4..a3a0e2282a56 100644
--- a/scripts/Makefile.host
+++ b/scripts/Makefile.host
@@ -84,7 +84,7 @@ hostcxx_flags  = -Wp,-MD,$(depfile) $(__hostcxx_flags)
 # Create executable from a single .c file
 # host-csingle -> Executable
 quiet_cmd_host-csingle 	= HOSTCC  $@
-      cmd_host-csingle	= $(HOSTCC) $(hostc_flags) -o $@ $< \
+      cmd_host-csingle	= $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -o $@ $< \
 	  	$(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F))
 $(host-csingle): $(obj)/%: $(src)/%.c FORCE
 	$(call if_changed_dep,host-csingle)
@@ -102,7 +102,7 @@ $(call multi_depend, $(host-cmulti), , -objs)
 # Create .o file from a single .c file
 # host-cobjs -> .o
 quiet_cmd_host-cobjs	= HOSTCC  $@
-      cmd_host-cobjs	= $(HOSTCC) $(hostc_flags) -c -o $@ $<
+      cmd_host-cobjs	= $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -c -o $@ $<
 $(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE
 	$(call if_changed_dep,host-cobjs)
 
@@ -126,7 +126,7 @@ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
 # Compile .c file, create position independent .o file
 # host-cshobjs -> .o
 quiet_cmd_host-cshobjs	= HOSTCC  -fPIC $@
-      cmd_host-cshobjs	= $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $<
+      cmd_host-cshobjs	= $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -fPIC -c -o $@ $<
 $(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE
 	$(call if_changed_dep,host-cshobjs)
 
diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
index cd72016c3cfa..cab55f0d90e1 100644
--- a/tools/build/Makefile.build
+++ b/tools/build/Makefile.build
@@ -64,7 +64,7 @@ quiet_cmd_cc_o_c = CC       $@
       cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 
 quiet_cmd_host_cc_o_c = HOSTCC   $@
-      cmd_host_cc_o_c = $(HOSTCC) $(host_c_flags) -c -o $@ $<
+      cmd_host_cc_o_c = $(HOSTCC) $(HOSTLDFLAGS) $(host_c_flags) -c -o $@ $<
 
 quiet_cmd_cxx_o_c = CXX      $@
       cmd_cxx_o_c = $(CXX) $(cxx_flags) -c -o $@ $<
-- 
2.16.2

[PATCH 2/3] objtool: Support HOSTCFLAGS and HOSTLDFLAGS

[Laura Abbott]

It may be useful to compile host programs with different flags (e.g.
hardening). Ensure that objtool picks up the appropriate flags.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
 tools/objtool/Makefile | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
index e6acc281dd37..0ff3bcac1ca9 100644
--- a/tools/objtool/Makefile
+++ b/tools/objtool/Makefile
@@ -31,8 +31,9 @@ INCLUDES := -I$(srctree)/tools/include \
 	    -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \
 	    -I$(srctree)/tools/objtool/arch/$(ARCH)/include
 WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed
-CFLAGS   += -Wall -Werror $(WARNINGS) -fomit-frame-pointer -O2 -g $(INCLUDES)
-LDFLAGS  += -lelf $(LIBSUBCMD)
+CFLAGS   += -Wall -Werror $(WARNINGS) $(HOSTCFLAGS) -fomit-frame-pointer -O2 -g \
+	    $(INCLUDES)
+LDFLAGS  += -lelf $(LIBSUBCMD) $(HOSTLDFLAGS)
 
 # Allow old libelf to be used:
 elfshdr := $(shell echo '\#include <libelf.h>' | $(CC) $(CFLAGS) -x c -E - | grep elf_getshdr)
-- 
2.16.2

[PATCH 3/3] kbuild: Allow passing additional HOSTCFLAGS and HOSTLDFLAGS

[Laura Abbott]

Similar to AFLAGS_KBUILD, there may be uses (e.g. hardening) for passing in
additional flags to host programs. Allow these to be passed in from the
environment.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
 Documentation/kbuild/kbuild.txt | 9 +++++++++
 Makefile                        | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt
index ac2363ea05c5..3751a4bc8596 100644
--- a/Documentation/kbuild/kbuild.txt
+++ b/Documentation/kbuild/kbuild.txt
@@ -24,6 +24,15 @@ KAFLAGS
 --------------------------------------------------
 Additional options to the assembler (for built-in and modules).
 
+AFLAGS_HOSTCFLAGS
+--------------------------------------------------
+Additional options passed to the compiler when building host programs.
+
+AFLAGS_HOSTLDFLAGS
+--------------------------------------------------
+Additional options passed to the linker (through the compiler) when buidling
+host programs.
+
 AFLAGS_MODULE
 --------------------------------------------------
 Additional module specific options to use for $(AS).
diff --git a/Makefile b/Makefile
index 7ba478ab8c82..2cab3f8d489c 100644
--- a/Makefile
+++ b/Makefile
@@ -367,6 +367,9 @@ HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
 HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
 HOST_LOADLIBES := $(HOST_LFS_LIBS)
 
+HOSTCFLAGS  += $(AFLAGS_HOSTCFLAGS)
+HOSTLDFLAGS  += $(AFLAGS_HOSTLDFLAGS)
+
 # Make variables (CC, etc...)
 AS		= $(CROSS_COMPILE)as
 LD		= $(CROSS_COMPILE)ld
-- 
2.16.2

Re: [PATCH 2/3] objtool: Support HOSTCFLAGS and HOSTLDFLAGS

[Masahiro Yamada]

2018-03-29 9:48 GMT+09:00 Laura Abbott <labbott@redhat.com>:
> It may be useful to compile host programs with different flags (e.g.
> hardening). Ensure that objtool picks up the appropriate flags.
>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---


I saw some similar patches before.

I thought they are fixing this way
https://patchwork.kernel.org/patch/10251259/

but, I am not tacking the progress.




>  tools/objtool/Makefile | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
> index e6acc281dd37..0ff3bcac1ca9 100644
> --- a/tools/objtool/Makefile
> +++ b/tools/objtool/Makefile
> @@ -31,8 +31,9 @@ INCLUDES := -I$(srctree)/tools/include \
>             -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \
>             -I$(srctree)/tools/objtool/arch/$(ARCH)/include
>  WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed
> -CFLAGS   += -Wall -Werror $(WARNINGS) -fomit-frame-pointer -O2 -g $(INCLUDES)
> -LDFLAGS  += -lelf $(LIBSUBCMD)
> +CFLAGS   += -Wall -Werror $(WARNINGS) $(HOSTCFLAGS) -fomit-frame-pointer -O2 -g \
> +           $(INCLUDES)
> +LDFLAGS  += -lelf $(LIBSUBCMD) $(HOSTLDFLAGS)
>
>  # Allow old libelf to be used:
>  elfshdr := $(shell echo '\#include <libelf.h>' | $(CC) $(CFLAGS) -x c -E - | grep elf_getshdr)
> --
> 2.16.2
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Best Regards
Masahiro Yamada

Re: [PATCH 3/3] kbuild: Allow passing additional HOSTCFLAGS and HOSTLDFLAGS

[Masahiro Yamada]

2018-03-29 9:48 GMT+09:00 Laura Abbott <labbott@redhat.com>:
>
> Similar to AFLAGS_KBUILD, there may be uses (e.g. hardening) for passing in
> additional flags to host programs. Allow these to be passed in from the
> environment.
>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
>  Documentation/kbuild/kbuild.txt | 9 +++++++++
>  Makefile                        | 3 +++
>  2 files changed, 12 insertions(+)
>
> diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt
> index ac2363ea05c5..3751a4bc8596 100644
> --- a/Documentation/kbuild/kbuild.txt
> +++ b/Documentation/kbuild/kbuild.txt
> @@ -24,6 +24,15 @@ KAFLAGS
>  --------------------------------------------------
>  Additional options to the assembler (for built-in and modules).
>
> +AFLAGS_HOSTCFLAGS
> +--------------------------------------------------
> +Additional options passed to the compiler when building host programs.
> +
> +AFLAGS_HOSTLDFLAGS
> +--------------------------------------------------
> +Additional options passed to the linker (through the compiler) when buidling
> +host programs.
> +


I am afraid you misunderstood the meaning of 'AFLAGS'.

AFLAGS is not 'Additional flags', but 'Assembler flags'
that are used for compiling *.S files.

AFLAGS for host programs is weird.



I see similar proposals from different people.

I replied like follows:
https://lkml.org/lkml/2018/2/28/178

However, Robin seems busy lately.

I will wait a bit, then
if nobody does this, I may do it.




>  AFLAGS_MODULE
>  --------------------------------------------------
>  Additional module specific options to use for $(AS).
> diff --git a/Makefile b/Makefile
> index 7ba478ab8c82..2cab3f8d489c 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -367,6 +367,9 @@ HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
>  HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
>  HOST_LOADLIBES := $(HOST_LFS_LIBS)
>
> +HOSTCFLAGS  += $(AFLAGS_HOSTCFLAGS)
> +HOSTLDFLAGS  += $(AFLAGS_HOSTLDFLAGS)
> +
>  # Make variables (CC, etc...)
>  AS             = $(CROSS_COMPILE)as
>  LD             = $(CROSS_COMPILE)ld
> --
> 2.16.2
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Best Regards
Masahiro Yamada

Re: [PATCH 1/3] kbuild: Support HOSTLDFLAGS

[Masahiro Yamada]

2018-03-29 9:48 GMT+09:00 Laura Abbott <labbott@redhat.com>:
>
> In addition to HOSTCFLAGS, there's HOSTLDFLAGS. Ensure these get passed to
> calls to build host binaries.
>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
>  scripts/Makefile.host      | 6 +++---
>  tools/build/Makefile.build | 2 +-
>  2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/scripts/Makefile.host b/scripts/Makefile.host
> index e6dc6ae2d7c4..a3a0e2282a56 100644
> --- a/scripts/Makefile.host
> +++ b/scripts/Makefile.host
> @@ -84,7 +84,7 @@ hostcxx_flags  = -Wp,-MD,$(depfile) $(__hostcxx_flags)
>  # Create executable from a single .c file
>  # host-csingle -> Executable
>  quiet_cmd_host-csingle         = HOSTCC  $@
> -      cmd_host-csingle = $(HOSTCC) $(hostc_flags) -o $@ $< \
> +      cmd_host-csingle = $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -o $@ $< \
>                 $(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F))
>  $(host-csingle): $(obj)/%: $(src)/%.c FORCE
>         $(call if_changed_dep,host-csingle)


This hunk is correct, but Robin posted this.
https://patchwork.kernel.org/patch/10243073/

Somehow it fell into a crack, and I missed to pick it up.
I will apply it lately.




> @@ -102,7 +102,7 @@ $(call multi_depend, $(host-cmulti), , -objs)
>  # Create .o file from a single .c file
>  # host-cobjs -> .o
>  quiet_cmd_host-cobjs   = HOSTCC  $@
> -      cmd_host-cobjs   = $(HOSTCC) $(hostc_flags) -c -o $@ $<
> +      cmd_host-cobjs   = $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -c -o $@ $<
>  $(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE
>         $(call if_changed_dep,host-cobjs)
>

This does not involve the link stage.
You should not do this.


> @@ -126,7 +126,7 @@ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
>  # Compile .c file, create position independent .o file
>  # host-cshobjs -> .o
>  quiet_cmd_host-cshobjs = HOSTCC  -fPIC $@
> -      cmd_host-cshobjs = $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $<
> +      cmd_host-cshobjs = $(HOSTCC) $(HOSTLDFLAGS) $(hostc_flags) -fPIC -c -o $@ $<
>  $(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE
>         $(call if_changed_dep,host-cshobjs)
>
> diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
> index cd72016c3cfa..cab55f0d90e1 100644
> --- a/tools/build/Makefile.build
> +++ b/tools/build/Makefile.build
> @@ -64,7 +64,7 @@ quiet_cmd_cc_o_c = CC       $@
>        cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
>
>  quiet_cmd_host_cc_o_c = HOSTCC   $@
> -      cmd_host_cc_o_c = $(HOSTCC) $(host_c_flags) -c -o $@ $<
> +      cmd_host_cc_o_c = $(HOSTCC) $(HOSTLDFLAGS) $(host_c_flags) -c -o $@ $<
>
>  quiet_cmd_cxx_o_c = CXX      $@
>        cmd_cxx_o_c = $(CXX) $(cxx_flags) -c -o $@ $<



-- 
Best Regards
Masahiro Yamada

Re: [PATCH 3/3] kbuild: Allow passing additional HOSTCFLAGS and HOSTLDFLAGS

[Laura Abbott]

On 04/04/2018 09:59 PM, Masahiro Yamada wrote:
> 2018-03-29 9:48 GMT+09:00 Laura Abbott <labbott@redhat.com>:
>>
>> Similar to AFLAGS_KBUILD, there may be uses (e.g. hardening) for passing in
>> additional flags to host programs. Allow these to be passed in from the
>> environment.
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
>>   Documentation/kbuild/kbuild.txt | 9 +++++++++
>>   Makefile                        | 3 +++
>>   2 files changed, 12 insertions(+)
>>
>> diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt
>> index ac2363ea05c5..3751a4bc8596 100644
>> --- a/Documentation/kbuild/kbuild.txt
>> +++ b/Documentation/kbuild/kbuild.txt
>> @@ -24,6 +24,15 @@ KAFLAGS
>>   --------------------------------------------------
>>   Additional options to the assembler (for built-in and modules).
>>
>> +AFLAGS_HOSTCFLAGS
>> +--------------------------------------------------
>> +Additional options passed to the compiler when building host programs.
>> +
>> +AFLAGS_HOSTLDFLAGS
>> +--------------------------------------------------
>> +Additional options passed to the linker (through the compiler) when buidling
>> +host programs.
>> +
> 
> 
> I am afraid you misunderstood the meaning of 'AFLAGS'.
> 
> AFLAGS is not 'Additional flags', but 'Assembler flags'
> that are used for compiling *.S files.
> 
> AFLAGS for host programs is weird.
> 
> 
> 
> I see similar proposals from different people.
> 
> I replied like follows:
> https://lkml.org/lkml/2018/2/28/178
> 
> However, Robin seems busy lately.
> 
> I will wait a bit, then
> if nobody does this, I may do it.
> 

Thanks for the pointer. I'll keep an eye out for those patches.

> 
> 
> 
>>   AFLAGS_MODULE
>>   --------------------------------------------------
>>   Additional module specific options to use for $(AS).
>> diff --git a/Makefile b/Makefile
>> index 7ba478ab8c82..2cab3f8d489c 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -367,6 +367,9 @@ HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS)
>>   HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS)
>>   HOST_LOADLIBES := $(HOST_LFS_LIBS)
>>
>> +HOSTCFLAGS  += $(AFLAGS_HOSTCFLAGS)
>> +HOSTLDFLAGS  += $(AFLAGS_HOSTLDFLAGS)
>> +
>>   # Make variables (CC, etc...)
>>   AS             = $(CROSS_COMPILE)as
>>   LD             = $(CROSS_COMPILE)ld
>> --
>> 2.16.2
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> 

Re: [PATCH 2/3] objtool: Support HOSTCFLAGS and HOSTLDFLAGS

[Laura Abbott]

On 04/04/2018 09:42 PM, Masahiro Yamada wrote:
> 2018-03-29 9:48 GMT+09:00 Laura Abbott <labbott@redhat.com>:
>> It may be useful to compile host programs with different flags (e.g.
>> hardening). Ensure that objtool picks up the appropriate flags.
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
> 
> 
> I saw some similar patches before.
> 
> I thought they are fixing this way
> https://patchwork.kernel.org/patch/10251259/
> 
> but, I am not tacking the progress.
> 
> 
> 

That looks like a different issue since it's still not going to
pick up the HOST{C,LD}FLAGS.

> 
>>   tools/objtool/Makefile | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
>> index e6acc281dd37..0ff3bcac1ca9 100644
>> --- a/tools/objtool/Makefile
>> +++ b/tools/objtool/Makefile
>> @@ -31,8 +31,9 @@ INCLUDES := -I$(srctree)/tools/include \
>>              -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \
>>              -I$(srctree)/tools/objtool/arch/$(ARCH)/include
>>   WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed
>> -CFLAGS   += -Wall -Werror $(WARNINGS) -fomit-frame-pointer -O2 -g $(INCLUDES)
>> -LDFLAGS  += -lelf $(LIBSUBCMD)
>> +CFLAGS   += -Wall -Werror $(WARNINGS) $(HOSTCFLAGS) -fomit-frame-pointer -O2 -g \
>> +           $(INCLUDES)
>> +LDFLAGS  += -lelf $(LIBSUBCMD) $(HOSTLDFLAGS)
>>
>>   # Allow old libelf to be used:
>>   elfshdr := $(shell echo '\#include <libelf.h>' | $(CC) $(CFLAGS) -x c -E - | grep elf_getshdr)
>> --
>> 2.16.2
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> 

Re: [PATCH 2/3] objtool: Support HOSTCFLAGS and HOSTLDFLAGS

[Josh Poimboeuf]

On Wed, Mar 28, 2018 at 05:48:04PM -0700, Laura Abbott wrote:
> It may be useful to compile host programs with different flags (e.g.
> hardening). Ensure that objtool picks up the appropriate flags.
> 
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
>  tools/objtool/Makefile | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
> index e6acc281dd37..0ff3bcac1ca9 100644
> --- a/tools/objtool/Makefile
> +++ b/tools/objtool/Makefile
> @@ -31,8 +31,9 @@ INCLUDES := -I$(srctree)/tools/include \
>  	    -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \
>  	    -I$(srctree)/tools/objtool/arch/$(ARCH)/include
>  WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed
> -CFLAGS   += -Wall -Werror $(WARNINGS) -fomit-frame-pointer -O2 -g $(INCLUDES)
> -LDFLAGS  += -lelf $(LIBSUBCMD)
> +CFLAGS   += -Wall -Werror $(WARNINGS) $(HOSTCFLAGS) -fomit-frame-pointer -O2 -g \
> +	    $(INCLUDES)

HOSTCFLAGS already has '-Wall', '-fomit-frame-pointer', and '-O2', so we
can remove the setting of those in CFLAGS here.

-- 
Josh