[PATCH] kbuild: move -gsplit-dwarf, -gdwarf-4 option tests to Kconfig

From: Masahiro Yamada
Date: Fri Feb 22 2019 - 02:56:32 EST


CONFIG_DEBUG_INFO_SPLIT and CONFIG_DEBUG_INFO_DWARF4 enable extra
dwarf options if supported. You never know if they are really enabled
since Makefile may silently turn them off.

The actual behavior will match to the kernel configuration by
testing those compiler flags in the Kconfig stage.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

Makefile | 4 ++--
lib/Kconfig.debug | 2 ++
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index bf4e77b..0f86257 100644
--- a/Makefile
+++ b/Makefile
@@ -735,14 +735,14 @@ DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments)

ifdef CONFIG_DEBUG_INFO
ifdef CONFIG_DEBUG_INFO_SPLIT
-DEBUG_CFLAGS += $(call cc-option, -gsplit-dwarf, -g)
+DEBUG_CFLAGS += -gsplit-dwarf
else
DEBUG_CFLAGS += -g
endif
KBUILD_AFLAGS += -Wa,-gdwarf-2
endif
ifdef CONFIG_DEBUG_INFO_DWARF4
-DEBUG_CFLAGS += $(call cc-option, -gdwarf-4,)
+DEBUG_CFLAGS += -gdwarf-4
endif

ifdef CONFIG_DEBUG_INFO_REDUCED
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d4df5b2..dfc9949 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -179,6 +179,7 @@ config DEBUG_INFO_REDUCED
config DEBUG_INFO_SPLIT
bool "Produce split debuginfo in .dwo files"
depends on DEBUG_INFO
+ depends on $(cc-option,-gsplit-dwarf)
help
Generate debug info into separate .dwo files. This significantly
reduces the build directory size for builds with DEBUG_INFO,
@@ -194,6 +195,7 @@ config DEBUG_INFO_SPLIT
config DEBUG_INFO_DWARF4
bool "Generate dwarf4 debuginfo"
depends on DEBUG_INFO
+ depends on $(cc-option,-gdwarf-4)
help
Generate dwarf4 debug info. This requires recent versions
of gcc and gdb. It makes the debug information larger.
--
2.7.4