New subject: [PATCH] Makefile: fix and simplify test program compilations

17 Aug 2011

Am 12.08.2011 21:38 schrieb Stefan Tauner:
...
this was totally broken due to the time behavior of make's shell
function's temporal behavior.
quote from the gnu make documentation
http://www.gnu.org/s/hello/manual/make/Shell-Function.html):
"The commands run by calls to the shell function are run when the
function calls are expanded"
we have used the shell function to echo the test programs to a file.
the file name used was equal for all tests and was overwritten for
each test. the result was that all tests (in a single target?) used
the last test program because the echoing of the test programs was
done before all test compilations(!)
Thanks for opening that bug report. Apparently the gnu make
documentation was incorrect.
...
also the branching for testing ifeq ($(CONFIG_FT2232_SPI), yes) was
unnecessary.
Branching never worked for me inside a target, but I also never tried it
your way.
...
in my approach here i am using verbatim variables (allows to define
even complex test programs in the makefile without jumping through
hoops) that get exported to environment variables (via "export",
reference afterwards with "$$<varname>").
i have also added the missing redirection of stderr to the compiler test.
Good.
...
alternatively one could just use different file names of course, but
i think my approach is superior due to the separation and
readability of the tested code and the fact that the temporal
behavior is MUCH clearer now (else this bug would have not crept in
in the first place :P)
if line count is an issue one could of course compress the test
programs to something unreadable again :)
Haha.
...
side note: we use $(CC) all over the place before we even check if
it is there. e.g.:
override ARCH = $(strip $(shell LC_ALL=C $(CC) -E arch.h|grep -v '^#'))
this creates unwanted output like:
make -j1 CC=eiugthes
/bin/sh: eiugthes: not found
/bin/sh: eiugthes: not found
/bin/sh: eiugthes: not found
/bin/sh: eiugthes: not found
Checking for a C compiler... not found.
Hm yes.
...
make: *** [compiler] Error 1
Signed-off-by: Stefan Tauner stefan.tauner@student.tuwien.ac.at
Makefile |   91 ++++++++++++++++++++++++++++++++++++++++----------------------
 1 files changed, 59 insertions(+), 32 deletions(-)

diff --git a/Makefile b/Makefile
index c72d10a..672a0df 100644
--- a/Makefile
+++ b/Makefile
@@ -531,11 +531,62 @@ distclean: clean
 strip: $(PROGRAM)$(EXEC_SUFFIX)
   $(STRIP) $(STRIP_ARGS) $(PROGRAM)$(EXEC_SUFFIX)
+# below are the definitions of test programs as verbatim variables, which get
+# exported to environment variables and are referenced with $$<varname> later
+define COMPILER_TEST
+int main(int argc, char **argv)
+{

(void) argafc;

Typo?
...
+define UTSNAME_TEST
+#include <sys/utsname.h>
+struct utsname osinfo;
+int main(int argc, char **argv)
+{

(void) argc;
(void) argv;
uname (&osinfo);
return 0;

+}
+endef
+export UTSNAME_TEST
Hm... the alternative would be to have each of those C programs in a
separate file in a config/ directory or somesuch. I don't have a strong
preference either way.
Given that you think verbatim variables are superior, please move them
directly above the targets which use them.
...



compiler: featuresavailable
   @printf "Checking for a C compiler... "

@$(shell ( echo "int main(int argc, char **argv)"; \
   echo "{ (void) argc; (void) argv; return 0; }"; ) > .test.c )


@$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) .test.c -o .test$(EXEC_SUFFIX) >/dev/null &&	\


@echo "$$COMPILER_TEST" > .test.c
@$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) .test.c -o .test$(EXEC_SUFFIX) >/dev/null 2>&1 &&	\
echo "found." || ( echo "not found."; \
rm -f .test.c .test$(EXEC_SUFFIX); exit 1)
@rm -f .test.c .test$(EXEC_SUFFIX)

@@ -548,12 +599,7 @@ compiler: featuresavailable
 ifeq ($(CHECK_LIBPCI), yes)
 pciutils: compiler
   @printf "Checking for libpci headers... "

@# Avoid a failing test due to libpci header symbol shadowing breakage
@$(shell ( echo "#define index shadow_workaround_index"; \
   echo "#include <pci/pci.h>";		   \


   echo "struct pci_access *pacc;";	   \


   echo "int main(int argc, char **argv)"; \


   echo "{ (void) argc; (void) argv; pacc = pci_alloc(); return 0; }"; ) > .test.c )




@echo "$$LIBPCI_TEST" > .test.c
@$(CC) -c $(CPPFLAGS) $(CFLAGS) .test.c -o .test.o >/dev/null 2>&1 &&		\
echo "found." || ( echo "not found."; echo;			\
echo "Please install libpci headers (package pciutils-devel).";	\

@@ -588,41 +634,22 @@ featuresavailable:
   @false
 endif
-ifeq ($(CONFIG_FT2232_SPI), yes)
 features: compiler
   @echo "FEATURES := yes" > .features.tmp
+ifeq ($(CONFIG_FT2232_SPI), yes)
I'm really surprised that ifeq inside a target works. IIRC I tried this
some time ago on my older machine and it did not work. However, if this
works reliably, the code is indeed a lot more readable.
Acked-by: Carl-Daniel Hailfinger c-d.hailfinger.devel.2006@gmx.net
Even if we ever decide to use another build system, we need this fix now.
Regards,
Carl-Daniel

    

Re: [flashrom] [PATCH] Makefile: fix and simplify test program compilations

Signed-off-by: Stefan Tauner stefan.tauner@student.tuwien.ac.at

Signed-off-by: Stefan Tauner stefan.tauner@student.tuwien.ac.at