tools: Allow building with debug enabled

Sometimes it is useful to build tools with debugging information included so
that line-number information is available when run under gdb. Add a Kconfig
option to support this.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NTom Rini <trini@konsulko.com>

Kconfig

@@ -114,6 +114,15 @@ if EXPERT
 	  Warning:
 	  When disabling this, please check if malloc calls, maybe
 	  should be replaced by calloc - if one expects zeroed memory.
+
+config TOOLS_DEBUG
+	bool "Enable debug information for tools"
+	help
+	  Enable generation of debug information for tools such as mkimage.
+	  This can be used for debugging purposes. With debug information
+	  it is possible to set breakpoints on particular lines, single-step
+	  debug through the source code, etc.
+
 endif
 endmenu		# General setup
 

Makefile

@@ -256,7 +256,8 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 
 HOSTCC       = cc
 HOSTCXX      = c++
-HOSTCFLAGS   = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer
+HOSTCFLAGS   = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer \
+		$(if $(CONFIG_TOOLS_DEBUG),-g)
 HOSTCXXFLAGS = -O2
 
 ifeq ($(HOSTOS),cygwin)