kbuild: convert include and source paths
RFC PATCH 3/6 kbuild: convert include and source paths
From: Peter Oberparleiter <[email protected]>
Modify kbuild to convert relative include and source paths to absolute form. Also change the module versioning mechanism to alter object file names only after compiling.
Required by the gcov profiling infrastructure: source paths are referenced by the compiled object files. Using relative paths or object file names which are different from the source name would prevent the gcov tool from finding the corresponding source files.
--- Makefile | 6 +++--- scripts/Kbuild.include | 2 ++ scripts/Makefile.build | 7 +++++-- scripts/Makefile.lib | 2 +- 4 files changed, 11 insertions(+), 6 deletions(-)
scripts/Makefile.build +5 -2
@@ -167,7 +167,8 @@ $(obj)/%.symtypes : $(src)/%.c FORCE quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ ifndef CONFIG_MODVERSIONS -cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< +cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ \ + $(if $(filter-out /%,$<),$(objtree)/$<,$<) else # When module versioning is enabled the following steps are executed:
@@ -182,7 +183,9 @@ else # replace the unresolved symbols __crc_exported_symbol with # the actual value of the checksum generated by genksyms -cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $< +cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/$(@F) \ + $(if $(filter-out /%,$<),$(objtree)/$<,$<) ; \ + mv -f $(@D)/$(@F) $(@D)/.tmp_$(@F) cmd_modversions = \ if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ $(CPP) -D__GENKSYMS__ $(c_flags) $< \
scripts/Makefile.lib +1 -1
@@ -113,7 +113,7 @@ else # $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files # and locates generated .h files # FIXME: Replace both with specific CFLAGS* statements in the makefiles -__c_flags = $(call addtree,-I$(obj)) $(call flags,_c_flags) +__c_flags = $(call addtree,-I$(obj)) $(call addtree2,-I$(obj)) $(call flags,_c_flags) __a_flags = $(call flags,_a_flags) __cpp_flags = $(call flags,_cpp_flags) endif
scripts/Kbuild.include +2 -0
@@ -145,6 +145,8 @@ build := -f $(if $(KBUILD_SRC),$(srctree # Prefix -I with $(srctree) if it is not an absolute path. addtree = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)) +# Prefix -I with $(objtree) if it is not an absolute path. +addtree2 = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(objtree)/%,$(1)),$(1)) # Find all -I options and call addtree flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
Makefile +3 -3
@@ -324,9 +324,9 @@ AFLAGS_KERNEL = # Use LINUXINCLUDE when you must reference the include/ directory. # Needed to be compatible with the O= option -LINUXINCLUDE := -Iinclude \ - $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \ - -include include/linux/autoconf.h +LINUXINCLUDE := -I$(objtree)/include -I$(srctree) -I$(objtree) \ + $(if $(KBUILD_SRC),-I$(objtree)/include2 \ + -I$(srctree)/include) -include include/linux/autoconf.h KBUILD_CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
Quoted 10 lines · Peter Oberparleiter
From: Peter Oberparleiter <[email protected]>
Modify kbuild to convert relative include and source paths to absolute form. Also change the module versioning mechanism to alter object file names only after compiling.
Required by the gcov profiling infrastructure: source paths are referenced by the compiled object files. Using relative paths or object file names which are different from the source name would prevent the gcov tool from finding the corresponding source files.
For the relative path issue do you really fix this at the right place? I would say that teaching gcov tool from where to look would be better.
Quoted 2 lines
Also change the module versioning mechanism to alter object file names only after compiling.
Can I get this as a separate patch please.
It may be general useful and makes sense to look at alone.
Sam
Quoted 77 lines · On Mon, 05 May 2008 17:24:26 +0200 Peter Oberparleiter…
From: Peter Oberparleiter <[email protected]>
Modify kbuild to convert relative include and source paths to absolute form. Also change the module versioning mechanism to alter object file names only after compiling.
Required by the gcov profiling infrastructure: source paths are referenced by the compiled object files. Using relative paths or object file names which are different from the source name would prevent the gcov tool from finding the corresponding source files.
Signed-off-by Peter Oberparleiter <[email protected]>--- Makefile | 6 +++--- scripts/Kbuild.include | 2 ++ scripts/Makefile.build | 7 +++++-- scripts/Makefile.lib | 2 +- 4 files changed, 11 insertions(+), 6 deletions(-)Index: linux-2.6.26-rc1/scripts/Makefile.build
===================================================================scripts/Makefile.build +5
-2@@ -167,7 +167,8 @@ $(obj)/%.symtypes : $(src)/%.c FORCE quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ ifndef CONFIG_MODVERSIONS -cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< +cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ \ + $(if $(filter-out /%,$<),$(objtree)/$<,$<) else # When module versioning is enabled the following steps are executed:@@ -182,7 +183,9 @@ else # replace the unresolved symbols __crc_exported_symbol with # the actual value of the checksum generated by genksyms -cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $< +cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/$(@F) \ + $(if $(filter-out /%,$<),$(objtree)/$<,$<) ; \ + mv -f $(@D)/$(@F) $(@D)/.tmp_$(@F) cmd_modversions = \ if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ $(CPP) -D__GENKSYMS__ $(c_flags) $< \Index: linux-2.6.26-rc1/scripts/Makefile.lib
===================================================================scripts/Makefile.lib +1
-1@@ -113,7 +113,7 @@ else # $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files # and locates generated .h files # FIXME: Replace both with specific CFLAGS* statements in the makefiles -__c_flags = $(call addtree,-I$(obj)) $(call flags,_c_flags) +__c_flags = $(call addtree,-I$(obj)) $(call addtree2,-I$(obj)) $(call flags,_c_flags) __a_flags = $(call flags,_a_flags) __cpp_flags = $(call flags,_cpp_flags) endifIndex: linux-2.6.26-rc1/scripts/Kbuild.include
===================================================================scripts/Kbuild.include +2
-0@@ -145,6 +145,8 @@ build := -f $(if $(KBUILD_SRC),$(srctree # Prefix -I with $(srctree) if it is not an absolute path. addtree = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)) +# Prefix -I with $(objtree) if it is not an absolute path. +addtree2 = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(objtree)/%,$(1)),$(1)) # Find all -I options and call addtree flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))Index: linux-2.6.26-rc1/Makefile
===================================================================Makefile +0
-0@@ -324,9 +324,9 @@ AFLAGS_KERNEL = # Use LINUXINCLUDE when you must reference the include/ directory.
Makefile AFLAGS_KERNEL = · line 332
Quoted 10 lines
Makefile +3
-3# Needed to be compatible with the O= option -LINUXINCLUDE := -Iinclude \ - $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \ - -include include/linux/autoconf.h +LINUXINCLUDE := -I$(objtree)/include -I$(srctree) -I$(objtree) \ + $(if $(KBUILD_SRC),-I$(objtree)/include2 \ + -I$(srctree)/include) -include include/linux/autoconf.h KBUILD_CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
I hope Sam understands that line-noise ;)
It doesn't appear to affect __FILE__ in any way (which is good). But I'm unsure what it _does_ affect. The changelog implies that it will convert "liunx/foo.h" into /usr/src/linux/include/foo.h, only it doesn't.
ho hum.
Quoted 7 lines · Sam Ravnborg
Quoted 6 lines · Peter Oberparleiter
From: Peter Oberparleiter <[email protected]>
Modify kbuild to convert relative include and source paths to absolute form. Also change the module versioning mechanism to alter object file names only after compiling.
Quoted 7 lines
Quoted 4 lines
Required by the gcov profiling infrastructure: source paths are referenced by the compiled object files. Using relative paths or object file names which are different from the source name would prevent the gcov tool from finding the corresponding source files.
For the relative path issue do you really fix this at the right place? I would say that teaching gcov tool from where to look would be better.
Actually it is gcc that would need to be changed to only include absolute paths in compiled object files. While I haven't led that particular discussion with gcc developers yet, I could imagine that they would argue that such an option already exists: by specifying only absolute paths during compilation. Also, any dependency on a future version of gcc would, in my opinion, greatly reduce the overall usefulness of this gcov kernel infrastructure.
Would it be acceptable to isolate these changes to kbuild by if-statements, i.e. use absolute paths only of CONFIG_GCOV is specified (as Jan Engelhardt suggested)?
Quoted 4 lines
Quoted 2 lines
Also change the module versioning mechanism to alter object file names only after compiling.
Can I get this as a separate patch please.
It may be general useful and makes sense to look at alone.
Ok, I will do that.
Regards,
Peter
Quoted 13 lines · Andrew Morton
Quoted 10 lines · On Mon, 05 May 2008 17:24:26 +0200 Peter Oberparleiter…
From: Peter Oberparleiter <[email protected]>
Modify kbuild to convert relative include and source paths to absolute form. Also change the module versioning mechanism to alter object file names only after compiling.
Required by the gcov profiling infrastructure: source paths are referenced by the compiled object files. Using relative paths or object file names which are different from the source name would prevent the gcov tool from finding the corresponding source files.
Quoted 5 lines
It doesn't appear to affect
__FILE__in any way (which is good). But I'm unsure what it _does_ affect. The changelog implies that it will convert "liunx/foo.h" into/usr/src/linux/include/foo.h, only it doesn't.ho hum.
This patch should convert
gcc -Idir1 -c a.c -o a.o
to
gcc -I/path/to/dir1 -c /path/to/a.c -o a.o
As a standalone change this has no visible effect, but when gcc option -fprofile-arcs is specified (as done in patch 5), the resulting object files should only contain absolute paths.
Regards,
Peter