diff mbox series

[v2,2/2] tools/resolve_btfids: Alter how HOSTCC is forced

Message ID 20230116215751.633675-2-irogers@google.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series [v2,1/2] tools/resolve_btfids: Install subcmd headers | expand

Checks

Context Check Description
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netdev/tree_selection success Not a local patch
bpf/vmtest-bpf-VM_Test-34 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-VM_Test-35 success Logs for test_verifier on aarch64 with llvm-16
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Commit Message

Ian Rogers Jan. 16, 2023, 9:57 p.m. UTC
HOSTCC is always wanted when building. Setting CC to HOSTCC happens
after tools/scripts/Makefile.include is included, meaning flags are
set assuming say CC is gcc, but then it can be later set to HOSTCC
which may be clang. tools/scripts/Makefile.include is needed for host
set up and common macros in objtool's Makefile. Rather than override
CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
builds and the linkage step. This means the Makefiles don't see things
like CC changing and tool flag determination, and similar, work
properly.

Also, clear the passed subdir as otherwise an outer build may break by
inadvertently passing an inappropriate value.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

Comments

Jiri Olsa Jan. 17, 2023, 10:07 p.m. UTC | #1
On Mon, Jan 16, 2023 at 01:57:51PM -0800, Ian Rogers wrote:
> HOSTCC is always wanted when building. Setting CC to HOSTCC happens
> after tools/scripts/Makefile.include is included, meaning flags are
> set assuming say CC is gcc, but then it can be later set to HOSTCC
> which may be clang. tools/scripts/Makefile.include is needed for host
> set up and common macros in objtool's Makefile. Rather than override
> CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
> builds and the linkage step. This means the Makefiles don't see things
> like CC changing and tool flag determination, and similar, work
> properly.
> 
> Also, clear the passed subdir as otherwise an outer build may break by
> inadvertently passing an inappropriate value.
> 
> Signed-off-by: Ian Rogers <irogers@google.com>

lgtm did you try cross build and build with clang?

jirka

> ---
>  tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
> index 76b737b2560d..515d87b32fb8 100644
> --- a/tools/bpf/resolve_btfids/Makefile
> +++ b/tools/bpf/resolve_btfids/Makefile
> @@ -18,14 +18,11 @@ else
>  endif
>  
>  # always use the host compiler
> -AR       = $(HOSTAR)
> -CC       = $(HOSTCC)
> -LD       = $(HOSTLD)
> -ARCH     = $(HOSTARCH)
> +HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
> +		  ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"
> +
>  RM      ?= rm
>  CROSS_COMPILE =
> -CFLAGS  := $(KBUILD_HOSTCFLAGS)
> -LDFLAGS := $(KBUILD_HOSTLDFLAGS)
>  
>  OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
>  
> @@ -56,12 +53,12 @@ $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
>  
>  $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
>  	$(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
> -		    DESTDIR=$(SUBCMD_DESTDIR) prefix= \
> +		    DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
>  		    $(abspath $@) install_headers
>  
>  $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
>  	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
> -		    DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
> +		    DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
>  		    $(abspath $@) install_headers
>  
>  CFLAGS += -g \
> @@ -76,11 +73,11 @@ export srctree OUTPUT CFLAGS Q
>  include $(srctree)/tools/build/Makefile.include
>  
>  $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
> -	$(Q)$(MAKE) $(build)=resolve_btfids
> +	$(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
>  
>  $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
>  	$(call msg,LINK,$@)
> -	$(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> +	$(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
>  
>  clean_objects := $(wildcard $(OUTPUT)/*.o                \
>                              $(OUTPUT)/.*.o.cmd           \
> -- 
> 2.39.0.314.g84b9a713c41-goog
>
Ian Rogers Jan. 17, 2023, 11:20 p.m. UTC | #2
On Tue, Jan 17, 2023 at 2:07 PM Jiri Olsa <olsajiri@gmail.com> wrote:
>
> On Mon, Jan 16, 2023 at 01:57:51PM -0800, Ian Rogers wrote:
> > HOSTCC is always wanted when building. Setting CC to HOSTCC happens
> > after tools/scripts/Makefile.include is included, meaning flags are
> > set assuming say CC is gcc, but then it can be later set to HOSTCC
> > which may be clang. tools/scripts/Makefile.include is needed for host
> > set up and common macros in objtool's Makefile. Rather than override
> > CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
> > builds and the linkage step. This means the Makefiles don't see things
> > like CC changing and tool flag determination, and similar, work
> > properly.
> >
> > Also, clear the passed subdir as otherwise an outer build may break by
> > inadvertently passing an inappropriate value.
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
>
> lgtm did you try cross build and build with clang?

Hmm.. I don't have a cross build but I checked clang. Any chance you
could check the cross build?

Thanks,
Ian

> jirka
>
> > ---
> >  tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
> >  1 file changed, 7 insertions(+), 10 deletions(-)
> >
> > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
> > index 76b737b2560d..515d87b32fb8 100644
> > --- a/tools/bpf/resolve_btfids/Makefile
> > +++ b/tools/bpf/resolve_btfids/Makefile
> > @@ -18,14 +18,11 @@ else
> >  endif
> >
> >  # always use the host compiler
> > -AR       = $(HOSTAR)
> > -CC       = $(HOSTCC)
> > -LD       = $(HOSTLD)
> > -ARCH     = $(HOSTARCH)
> > +HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
> > +               ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"
> > +
> >  RM      ?= rm
> >  CROSS_COMPILE =
> > -CFLAGS  := $(KBUILD_HOSTCFLAGS)
> > -LDFLAGS := $(KBUILD_HOSTLDFLAGS)
> >
> >  OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
> >
> > @@ -56,12 +53,12 @@ $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
> >
> >  $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
> >       $(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
> > -                 DESTDIR=$(SUBCMD_DESTDIR) prefix= \
> > +                 DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> >                   $(abspath $@) install_headers
> >
> >  $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
> >       $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
> > -                 DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
> > +                 DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> >                   $(abspath $@) install_headers
> >
> >  CFLAGS += -g \
> > @@ -76,11 +73,11 @@ export srctree OUTPUT CFLAGS Q
> >  include $(srctree)/tools/build/Makefile.include
> >
> >  $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
> > -     $(Q)$(MAKE) $(build)=resolve_btfids
> > +     $(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
> >
> >  $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
> >       $(call msg,LINK,$@)
> > -     $(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> > +     $(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> >
> >  clean_objects := $(wildcard $(OUTPUT)/*.o                \
> >                              $(OUTPUT)/.*.o.cmd           \
> > --
> > 2.39.0.314.g84b9a713c41-goog
> >
Jiri Olsa Jan. 18, 2023, 10:30 p.m. UTC | #3
On Tue, Jan 17, 2023 at 03:20:38PM -0800, Ian Rogers wrote:
> On Tue, Jan 17, 2023 at 2:07 PM Jiri Olsa <olsajiri@gmail.com> wrote:
> >
> > On Mon, Jan 16, 2023 at 01:57:51PM -0800, Ian Rogers wrote:
> > > HOSTCC is always wanted when building. Setting CC to HOSTCC happens
> > > after tools/scripts/Makefile.include is included, meaning flags are
> > > set assuming say CC is gcc, but then it can be later set to HOSTCC
> > > which may be clang. tools/scripts/Makefile.include is needed for host
> > > set up and common macros in objtool's Makefile. Rather than override
> > > CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
> > > builds and the linkage step. This means the Makefiles don't see things
> > > like CC changing and tool flag determination, and similar, work
> > > properly.
> > >
> > > Also, clear the passed subdir as otherwise an outer build may break by
> > > inadvertently passing an inappropriate value.
> > >
> > > Signed-off-by: Ian Rogers <irogers@google.com>
> >
> > lgtm did you try cross build and build with clang?
> 
> Hmm.. I don't have a cross build but I checked clang. Any chance you
> could check the cross build?

ok, I'll try tomorrow

jirka

> 
> Thanks,
> Ian
> 
> > jirka
> >
> > > ---
> > >  tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
> > >  1 file changed, 7 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
> > > index 76b737b2560d..515d87b32fb8 100644
> > > --- a/tools/bpf/resolve_btfids/Makefile
> > > +++ b/tools/bpf/resolve_btfids/Makefile
> > > @@ -18,14 +18,11 @@ else
> > >  endif
> > >
> > >  # always use the host compiler
> > > -AR       = $(HOSTAR)
> > > -CC       = $(HOSTCC)
> > > -LD       = $(HOSTLD)
> > > -ARCH     = $(HOSTARCH)
> > > +HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
> > > +               ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"
> > > +
> > >  RM      ?= rm
> > >  CROSS_COMPILE =
> > > -CFLAGS  := $(KBUILD_HOSTCFLAGS)
> > > -LDFLAGS := $(KBUILD_HOSTLDFLAGS)
> > >
> > >  OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
> > >
> > > @@ -56,12 +53,12 @@ $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
> > >
> > >  $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
> > >       $(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
> > > -                 DESTDIR=$(SUBCMD_DESTDIR) prefix= \
> > > +                 DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> > >                   $(abspath $@) install_headers
> > >
> > >  $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
> > >       $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
> > > -                 DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
> > > +                 DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> > >                   $(abspath $@) install_headers
> > >
> > >  CFLAGS += -g \
> > > @@ -76,11 +73,11 @@ export srctree OUTPUT CFLAGS Q
> > >  include $(srctree)/tools/build/Makefile.include
> > >
> > >  $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
> > > -     $(Q)$(MAKE) $(build)=resolve_btfids
> > > +     $(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
> > >
> > >  $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
> > >       $(call msg,LINK,$@)
> > > -     $(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> > > +     $(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> > >
> > >  clean_objects := $(wildcard $(OUTPUT)/*.o                \
> > >                              $(OUTPUT)/.*.o.cmd           \
> > > --
> > > 2.39.0.314.g84b9a713c41-goog
> > >
Jiri Olsa Jan. 19, 2023, 2:51 p.m. UTC | #4
On Mon, Jan 16, 2023 at 01:57:51PM -0800, Ian Rogers wrote:
> HOSTCC is always wanted when building. Setting CC to HOSTCC happens
> after tools/scripts/Makefile.include is included, meaning flags are
> set assuming say CC is gcc, but then it can be later set to HOSTCC
> which may be clang. tools/scripts/Makefile.include is needed for host
> set up and common macros in objtool's Makefile. Rather than override
> CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
> builds and the linkage step. This means the Makefiles don't see things
> like CC changing and tool flag determination, and similar, work
> properly.
> 
> Also, clear the passed subdir as otherwise an outer build may break by
> inadvertently passing an inappropriate value.

I tested with cross builds for s390/ppc/arm64 and it was ok

some comments below

thanks,
jirka


> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
> index 76b737b2560d..515d87b32fb8 100644
> --- a/tools/bpf/resolve_btfids/Makefile
> +++ b/tools/bpf/resolve_btfids/Makefile
> @@ -18,14 +18,11 @@ else
>  endif
>  
>  # always use the host compiler
> -AR       = $(HOSTAR)
> -CC       = $(HOSTCC)
> -LD       = $(HOSTLD)
> -ARCH     = $(HOSTARCH)

I wonder all the tools should use HOSTCC in the first place?
seems more clear than forcing it from other makefiles

subcmd even has:

CC ?= $(CROSS_COMPILE)gcc
LD ?= $(CROSS_COMPILE)ld
AR ?= $(CROSS_COMPILE)ar

which seems wrong unless I'm missing something.. should be always
the host compiler, right?

> +HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
> +		  ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"

there's extra AR set and ARCH value is not in ""

> +
>  RM      ?= rm
>  CROSS_COMPILE =
> -CFLAGS  := $(KBUILD_HOSTCFLAGS)
> -LDFLAGS := $(KBUILD_HOSTLDFLAGS)
>  
>  OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
>  
> @@ -56,12 +53,12 @@ $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
>  
>  $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
>  	$(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
> -		    DESTDIR=$(SUBCMD_DESTDIR) prefix= \
> +		    DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
>  		    $(abspath $@) install_headers
>  
>  $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
>  	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
> -		    DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
> +		    DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
>  		    $(abspath $@) install_headers
>  
>  CFLAGS += -g \
> @@ -76,11 +73,11 @@ export srctree OUTPUT CFLAGS Q
>  include $(srctree)/tools/build/Makefile.include
>  
>  $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
> -	$(Q)$(MAKE) $(build)=resolve_btfids
> +	$(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
>  
>  $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
>  	$(call msg,LINK,$@)
> -	$(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> +	$(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
>  
>  clean_objects := $(wildcard $(OUTPUT)/*.o                \
>                              $(OUTPUT)/.*.o.cmd           \
> -- 
> 2.39.0.314.g84b9a713c41-goog
>
Ian Rogers Jan. 19, 2023, 6:13 p.m. UTC | #5
On Thu, Jan 19, 2023 at 6:51 AM Jiri Olsa <olsajiri@gmail.com> wrote:
>
> On Mon, Jan 16, 2023 at 01:57:51PM -0800, Ian Rogers wrote:
> > HOSTCC is always wanted when building. Setting CC to HOSTCC happens
> > after tools/scripts/Makefile.include is included, meaning flags are
> > set assuming say CC is gcc, but then it can be later set to HOSTCC
> > which may be clang. tools/scripts/Makefile.include is needed for host
> > set up and common macros in objtool's Makefile. Rather than override
> > CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
> > builds and the linkage step. This means the Makefiles don't see things
> > like CC changing and tool flag determination, and similar, work
> > properly.
> >
> > Also, clear the passed subdir as otherwise an outer build may break by
> > inadvertently passing an inappropriate value.
>
> I tested with cross builds for s390/ppc/arm64 and it was ok
>
> some comments below
>
> thanks,
> jirka
>
>
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
> > ---
> >  tools/bpf/resolve_btfids/Makefile | 17 +++++++----------
> >  1 file changed, 7 insertions(+), 10 deletions(-)
> >
> > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
> > index 76b737b2560d..515d87b32fb8 100644
> > --- a/tools/bpf/resolve_btfids/Makefile
> > +++ b/tools/bpf/resolve_btfids/Makefile
> > @@ -18,14 +18,11 @@ else
> >  endif
> >
> >  # always use the host compiler
> > -AR       = $(HOSTAR)
> > -CC       = $(HOSTCC)
> > -LD       = $(HOSTLD)
> > -ARCH     = $(HOSTARCH)
>
> I wonder all the tools should use HOSTCC in the first place?
> seems more clear than forcing it from other makefiles
>
> subcmd even has:
>
> CC ?= $(CROSS_COMPILE)gcc
> LD ?= $(CROSS_COMPILE)ld
> AR ?= $(CROSS_COMPILE)ar
>
> which seems wrong unless I'm missing something.. should be always
> the host compiler, right?

Hmm.. it seems like a feature to be able to cross compile things like
the perf tool.

I agree the way this is all done is muddling and we should try to keep
the way it is done consistent. The pattern of always early including
Makefile.include, that sets flags based on CC, but then overriding CC
was what I was after cleaning up here. Let's work on migrating to
something better.

> > +HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
> > +               ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"
>
> there's extra AR set and ARCH value is not in ""

Ack. Will fix in v3.

Thanks,
Ian


> > +
> >  RM      ?= rm
> >  CROSS_COMPILE =
> > -CFLAGS  := $(KBUILD_HOSTCFLAGS)
> > -LDFLAGS := $(KBUILD_HOSTLDFLAGS)
> >
> >  OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
> >
> > @@ -56,12 +53,12 @@ $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
> >
> >  $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
> >       $(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
> > -                 DESTDIR=$(SUBCMD_DESTDIR) prefix= \
> > +                 DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> >                   $(abspath $@) install_headers
> >
> >  $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
> >       $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
> > -                 DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
> > +                 DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
> >                   $(abspath $@) install_headers
> >
> >  CFLAGS += -g \
> > @@ -76,11 +73,11 @@ export srctree OUTPUT CFLAGS Q
> >  include $(srctree)/tools/build/Makefile.include
> >
> >  $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
> > -     $(Q)$(MAKE) $(build)=resolve_btfids
> > +     $(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
> >
> >  $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
> >       $(call msg,LINK,$@)
> > -     $(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> > +     $(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
> >
> >  clean_objects := $(wildcard $(OUTPUT)/*.o                \
> >                              $(OUTPUT)/.*.o.cmd           \
> > --
> > 2.39.0.314.g84b9a713c41-goog
> >
diff mbox series

Patch

diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile
index 76b737b2560d..515d87b32fb8 100644
--- a/tools/bpf/resolve_btfids/Makefile
+++ b/tools/bpf/resolve_btfids/Makefile
@@ -18,14 +18,11 @@  else
 endif
 
 # always use the host compiler
-AR       = $(HOSTAR)
-CC       = $(HOSTCC)
-LD       = $(HOSTLD)
-ARCH     = $(HOSTARCH)
+HOST_OVERRIDES := AR=$(HOSTAR) CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
+		  ARCH=$(HOSTARCH) EXTRA_CFLAGS="$(HOSTCFLAGS) $(KBUILD_HOSTCFLAGS)"
+
 RM      ?= rm
 CROSS_COMPILE =
-CFLAGS  := $(KBUILD_HOSTCFLAGS)
-LDFLAGS := $(KBUILD_HOSTLDFLAGS)
 
 OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/
 
@@ -56,12 +53,12 @@  $(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT):
 
 $(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd
 	$(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \
-		    DESTDIR=$(SUBCMD_DESTDIR) prefix= \
+		    DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
 		    $(abspath $@) install_headers
 
 $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT)
 	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT)    \
-		    DESTDIR=$(LIBBPF_DESTDIR) prefix= EXTRA_CFLAGS="$(CFLAGS)" \
+		    DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \
 		    $(abspath $@) install_headers
 
 CFLAGS += -g \
@@ -76,11 +73,11 @@  export srctree OUTPUT CFLAGS Q
 include $(srctree)/tools/build/Makefile.include
 
 $(BINARY_IN): fixdep FORCE prepare | $(OUTPUT)
-	$(Q)$(MAKE) $(build)=resolve_btfids
+	$(Q)$(MAKE) $(build)=resolve_btfids $(HOST_OVERRIDES)
 
 $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)
 	$(call msg,LINK,$@)
-	$(Q)$(CC) $(BINARY_IN) $(LDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
+	$(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS)
 
 clean_objects := $(wildcard $(OUTPUT)/*.o                \
                             $(OUTPUT)/.*.o.cmd           \