Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 17c568d6 authored by Frantisek Hrbata's avatar Frantisek Hrbata Committed by Linus Torvalds
Browse files

gcov: compile specific gcov implementation based on gcc version 



Compile the correct gcov implementation file for the specific gcc version.

Signed-off-by: default avatarFrantisek Hrbata <fhrbata@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: default avatarPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Gospodarek <agospoda@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5f41ea03

Documentation/gcov.txt

+4 −0
Original line number Diff line number Diff line
@@ -50,6 +50,10 @@ Configure the kernel with: 
        CONFIG_DEBUG_FS=y

        CONFIG_GCOV_KERNEL=y



select the gcc's gcov format, default is autodetect based on gcc version:



        CONFIG_GCOV_FORMAT_AUTODETECT=y



and to get coverage data for the entire kernel:



        CONFIG_GCOV_PROFILE_ALL=y

kernel/gcov/Kconfig

+30 −0
Original line number Diff line number Diff line
@@ -46,4 +46,34 @@ config GCOV_PROFILE_ALL 
	larger and run slower. Also be sure to exclude files from profiling

	which are not linked to the kernel image to prevent linker errors.



choice

	prompt "Specify GCOV format"

	depends on GCOV_KERNEL

	default GCOV_FORMAT_AUTODETECT

	---help---

	The gcov format is usually determined by the GCC version, but there are

	exceptions where format changes are integrated in lower-version GCCs.

	In such a case use this option to adjust the format used in the kernel

	accordingly.



	If unsure, choose "Autodetect".



config GCOV_FORMAT_AUTODETECT

	bool "Autodetect"

	---help---

	Select this option to use the format that corresponds to your GCC

	version.



config GCOV_FORMAT_3_4

	bool "GCC 3.4 format"

	---help---

	Select this option to use the format defined by GCC 3.4.



config GCOV_FORMAT_4_7

	bool "GCC 4.7 format"

	---help---

	Select this option to use the format defined by GCC 4.7.



endchoice



endmenu

kernel/gcov/Makefile

+31 −1
Original line number Diff line number Diff line 
ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"'



obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o gcc_3_4.o
 
# if-lt

# Usage VAR := $(call if-lt, $(a), $(b))

# Returns 1 if (a < b)

if-lt = $(shell [ $(1) -lt $(2) ] && echo 1)



ifeq ($(CONFIG_GCOV_FORMAT_3_4),y)

  cc-ver := 0304

else ifeq ($(CONFIG_GCOV_FORMAT_4_7),y)

  cc-ver := 0407

else

# Use cc-version if available, otherwise set 0

#

# scripts/Kbuild.include, which contains cc-version function, is not included

# during make clean "make -f scripts/Makefile.clean obj=kernel/gcov"

# Meaning cc-ver is empty causing if-lt test to fail with

# "/bin/sh: line 0: [: -lt: unary operator expected" error mesage.

# This has no affect on the clean phase, but the error message could be

# confusing/annoying. So this dummy workaround sets cc-ver to zero if cc-version

# is not available. We can probably move if-lt to Kbuild.include, so it's also

# not defined during clean or to include Kbuild.include in

# scripts/Makefile.clean. But the following workaround seems least invasive.

  cc-ver := $(if $(call cc-version),$(call cc-version),0)

endif



obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o



ifeq ($(call if-lt, $(cc-ver), 0407),1)

  obj-$(CONFIG_GCOV_KERNEL) += gcc_3_4.o

else

  obj-$(CONFIG_GCOV_KERNEL) += gcc_4_7.o

endif