Change in flashrom[staging]: Fix standalone ich_descriptor_tool compilation with MinGW and DJGPP

[Nico Huber (Code Review)]

Nico Huber has submitted this change and it was merged. ( https://review.coreboot.org/21838 )

Change subject: Fix standalone ich_descriptor_tool compilation with MinGW and DJGPP
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Fix standalone ich_descriptor_tool compilation with MinGW and DJGPP

TARGET_OS as well as EXEC_SUFFIX were only set when called via the
main makefile and even then __USE_MINGW_ANSI_STDIO was not set
for MinGW.

While at it, also replace the hardcoded gnu_printf printf format
attribute with __MINGW_PRINTF_FORMAT which is set according to
__USE_MINGW_ANSI_STDIO respectively.

Change-Id: Id146f5ba06a0e510397c6f32a2bd7c819a405a25
Signed-off-by: Stefan Tauner 
Reviewed-on: https://review.coreboot.org/21838
Tested-by: build bot (Jenkins) 
Reviewed-by: Nico Huber 
---
M flash.h
M util/ich_descriptors_tool/Makefile
2 files changed, 14 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Nico Huber: Looks good to me, approved

diff --git a/flash.h b/flash.h
index dfda9d2..62f2e34 100644
--- a/flash.h
+++ b/flash.h
@@ -333,7 +333,7 @@
 /* Let gcc and clang check for correct printf-style format strings. */
 int print(enum flashrom_log_level level, const char *fmt, ...)
 #ifdef __MINGW32__
-__attribute__((format(gnu_printf, 2, 3)));
+__attribute__((format(__MINGW_PRINTF_FORMAT, 2, 3)));
 #else
 __attribute__((format(printf, 2, 3)));
 #endif
diff --git a/util/ich_descriptors_tool/Makefile b/util/ich_descriptors_tool/Makefile
index e312996..d1b5eae 100644
--- a/util/ich_descriptors_tool/Makefile
+++ b/util/ich_descriptors_tool/Makefile
@@ -21,10 +21,23 @@
 # If the user has specified custom CFLAGS, all CFLAGS settings below will be
 # completely ignored by gnumake.
 CFLAGS ?= -Os -Wall -Wshadow
+
+override TARGET_OS := $(shell $(CC) $(CPPFLAGS) -E $(SHAREDSRCDIR)/os.h | grep -v '^#' | grep '"' | \
+			cut -f 2 -d'"')
+
 ifeq ($(TARGET_OS), DOS)
+EXEC_SUFFIX := .exe
 # DJGPP has odd uint*_t definitions which cause lots of format string warnings.
 CFLAGS += -Wno-format
 endif
+
+ifeq ($(TARGET_OS), MinGW)
+EXEC_SUFFIX := .exe
+# Some functions provided by Microsoft do not work as described in C99 specifications. This macro fixes that
+# for MinGW. See http://sourceforge.net/p/mingw-w64/wiki2/printf%20and%20scanf%20family/ */
+FLASHROM_CFLAGS += -D__USE_MINGW_ANSI_STDIO=1
+endif
+
 ifeq ($(WARNERROR), yes)
 CFLAGS += -Werror
 endif