perf tools: Reorganize the Makefile feature tests

Moving the tests to a separate file, feature-tests.mak and using a try-cc
function similar to the try-run in Kbuild.

This also makes the output more quiet as we can stop using the INTERMEDIATE
target to remove the .perf.dev.null file needed for some gcc versions where
/dev/null can't be used as the output file name.

As the tests get shorter by uninlining the source code used to test for
features, we can more properly use identation.

The feature tests itself can be made more clear and reused, like when trying to
see what is needed to have bfd_demangle.

We also get a bit closer to reusing scripts/Kbuild.include, reducing the
distance from the kernel build system.

Tests performed:

[root@emilia perf]# make -j9 O=/tmp/perf
PERF_VERSION = 0.0.2.PERF
    GEN /tmp/perf/common-cmds.h
    * new build flags or prefix
    GEN perf-archive
    CC /tmp/perf/builtin-annotate.o
    CC /tmp/perf/bench/sched-messaging.o
    CC /tmp/perf/builtin-diff.o
<SNIP>
    CC /tmp/perf/scripts/python/Perf-Trace-Util/Context.o
    CC /tmp/perf/perf.o
    CC /tmp/perf/builtin-help.o
    AR /tmp/perf/libperf.a
    LINK /tmp/perf/perf
[root@emilia perf]#

If we uninstall, for instance newt-devel we get:

[root@emilia perf]# rpm -e newt-devel
[root@emilia perf]# make -j9 O=/tmp/perf
Makefile:564: newt not found, disables TUI support. Please install newt-devel or libnewt-dev
    * new build flags or prefix
    GEN perf-archive
    CC /tmp/perf/perf.o
    CC /tmp/perf/builtin-annotate.o
<SNIP>
    AR /tmp/perf/libperf.a
    LINK /tmp/perf/perf
[root@emilia perf]#

And then binutils-devel:

[root@emilia perf]# make -j9 O=/tmp/perf
Makefile:564: newt not found, disables TUI support. Please install newt-devel or libnewt-dev
Makefile:632: No bfd.h/libbfd found, install binutils-dev[el]/zlib-static to gain symbol demangling
    * new build flags or prefix
    GEN perf-archive
    CC /tmp/perf/perf.o
<SNIP>
    AR /tmp/perf/libperf.a
    LINK /tmp/perf/perf
[root@emilia perf]#

And then strictly required devel packages:

[root@emilia perf]# rpm -e elfutils-libelf-devel elfutils-devel
[root@emilia perf]# make -j9 O=/tmp/perf
Makefile:509: No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev
Makefile:542: *** No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel.  Stop.
[root@emilia perf]#

After installing everything back on:

[root@emilia perf]# yum install elfutils-devel binutils-devel newt-devel
<SNIP>
Installed:
  binutils-devel.x86_64 0:2.20.51.0.2-5.11.el6
  elfutils-devel.x86_64 0:0.147-1.el6
  elfutils-libelf-devel.x86_64 0:0.147-1.el6
  newt-devel.x86_64 0:0.52.11-1.el6

Complete!
[root@emilia perf]# make -j9
PERF_VERSION = 0.0.2.PERF
    GEN common-cmds.h
    * new build flags or prefix
    GEN perf-archive
    CC builtin-annotate.o
<SNIP>
    AR libperf.a
    LINK perf
[root@emilia perf]# make -j9
[root@emilia perf]#

Thanks to Sam for pointing me to try-run.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile

@@ -285,14 +285,10 @@ else
 	QUIET_STDERR = ">/dev/null 2>&1"
 endif
 
-BITBUCKET = "/dev/null"
+-include feature-tests.mak
 
-ifneq ($(shell sh -c "(echo '\#include <stdio.h>'; echo 'int main(void) { return puts(\"hi\"); }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) "$(QUIET_STDERR)" && echo y"), y)
-	BITBUCKET = .perf.dev.null
-endif
-
-ifeq ($(shell sh -c "echo 'int foo(void) {char X[2]; return 3;}' | $(CC) -x c -c -Werror -fstack-protector-all - -o $(BITBUCKET) "$(QUIET_STDERR)" && echo y"), y)
-  CFLAGS := $(CFLAGS) -fstack-protector-all
+ifeq ($(call try-cc,$(SOURCE_HELLO),-Werror -fstack-protector-all),y)
+	CFLAGS := $(CFLAGS) -fstack-protector-all
 endif
 
 
@@ -508,7 +504,8 @@ PERFLIBS = $(LIB_FILE)
 -include config.mak
 
 ifndef NO_DWARF
-ifneq ($(shell sh -c "(echo '\#include <dwarf.h>'; echo '\#include <libdw.h>'; echo '\#include <version.h>'; echo '\#ifndef _ELFUTILS_PREREQ'; echo '\#error'; echo '\#endif'; echo 'int main(void) { Dwarf *dbg; dbg = dwarf_begin(0, DWARF_C_READ); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -I/usr/include/elfutils -ldw -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
+FLAGS_DWARF=$(ALL_CFLAGS) -I/usr/include/elfutils -ldw -lelf $(ALL_LDFLAGS) $(EXTLIBS)
+ifneq ($(call try-cc,$(SOURCE_DWARF),$(FLAGS_DWARF)),y)
 	msg := $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev);
 	NO_DWARF := 1
 endif # Dwarf support
@@ -536,16 +533,18 @@ ifneq ($(OUTPUT),)
 	BASIC_CFLAGS += -I$(OUTPUT)
 endif
 
-ifeq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-ifneq ($(shell sh -c "(echo '\#include <gnu/libc-version.h>'; echo 'int main(void) { const char * version = gnu_get_libc_version(); return (long)version; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-	msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static);
+FLAGS_LIBELF=$(ALL_CFLAGS) $(ALL_LDFLAGS) $(EXTLIBS)
+ifneq ($(call try-cc,$(SOURCE_LIBELF),$(FLAGS_LIBELF)),y)
+	FLAGS_GLIBC=$(ALL_CFLAGS) $(ALL_LDFLAGS)
+	ifneq ($(call try-cc,$(SOURCE_GLIBC),$(FLAGS_GLIBC)),y)
+		msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static);
+	else
+		msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel);
+	endif
 endif
 
-	ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-		BASIC_CFLAGS += -DLIBELF_NO_MMAP
-	endif
-else
-	msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel and glibc-dev[el]);
+ifneq ($(call try-cc,$(SOURCE_ELF_MMAP),$(FLAGS_COMMON)),y)
+	BASIC_CFLAGS += -DLIBELF_NO_MMAP
 endif
 
 ifndef NO_DWARF
@@ -561,41 +560,47 @@ endif # NO_DWARF
 ifdef NO_NEWT
 	BASIC_CFLAGS += -DNO_NEWT_SUPPORT
 else
-ifneq ($(shell sh -c "(echo '\#include <newt.h>'; echo 'int main(void) { newtInit(); newtCls(); return newtFinished(); }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -lnewt -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y)
-	msg := $(warning newt not found, disables TUI support. Please install newt-devel or libnewt-dev);
-	BASIC_CFLAGS += -DNO_NEWT_SUPPORT
-else
-	# Fedora has /usr/include/slang/slang.h, but ubuntu /usr/include/slang.h
-	BASIC_CFLAGS += -I/usr/include/slang
-	EXTLIBS += -lnewt -lslang
-	LIB_OBJS += $(OUTPUT)util/newt.o
-endif
-endif # NO_NEWT
-
-ifndef NO_LIBPERL
-PERL_EMBED_LDOPTS = `perl -MExtUtils::Embed -e ldopts 2>/dev/null`
-PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null`
+	FLAGS_NEWT=$(ALL_CFLAGS) $(ALL_LDFLAGS) $(EXTLIBS) -lnewt
+	ifneq ($(call try-cc,$(SOURCE_NEWT),$(FLAGS_NEWT)),y)
+		msg := $(warning newt not found, disables TUI support. Please install newt-devel or libnewt-dev);
+		BASIC_CFLAGS += -DNO_NEWT_SUPPORT
+	else
+		# Fedora has /usr/include/slang/slang.h, but ubuntu /usr/include/slang.h
+		BASIC_CFLAGS += -I/usr/include/slang
+		EXTLIBS += -lnewt -lslang
+		LIB_OBJS += $(OUTPUT)util/newt.o
+	endif
 endif
 
-ifneq ($(shell sh -c "(echo '\#include <EXTERN.h>'; echo '\#include <perl.h>'; echo 'int main(void) { perl_alloc(); return 0; }') | $(CC) -x c - $(PERL_EMBED_CCOPTS) -o $(BITBUCKET) $(PERL_EMBED_LDOPTS) > /dev/null 2>&1 && echo y"), y)
+ifdef NO_LIBPERL
 	BASIC_CFLAGS += -DNO_LIBPERL
 else
-	ALL_LDFLAGS += $(PERL_EMBED_LDOPTS)
-	LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-perl.o
-	LIB_OBJS += $(OUTPUT)scripts/perl/Perf-Trace-Util/Context.o
-endif
+	PERL_EMBED_LDOPTS = `perl -MExtUtils::Embed -e ldopts 2>/dev/null`
+	PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null`
+	PERL_EMBED_FLAGS=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS)
 
-ifndef NO_LIBPYTHON
-PYTHON_EMBED_LDOPTS = `python-config --ldflags 2>/dev/null`
-PYTHON_EMBED_CCOPTS = `python-config --cflags 2>/dev/null`
+	ifneq ($(call try-cc,$(SOURCE_PERL_EMBED),$(FLAGS_PERL_EMBED)),y)
+		BASIC_CFLAGS += -DNO_LIBPERL
+	else
+		ALL_LDFLAGS += $(PERL_EMBED_LDOPTS)
+		LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-perl.o
+		LIB_OBJS += $(OUTPUT)scripts/perl/Perf-Trace-Util/Context.o
+	endif
 endif
 
-ifneq ($(shell sh -c "(echo '\#include <Python.h>'; echo 'int main(void) { Py_Initialize(); return 0; }') | $(CC) -x c - $(PYTHON_EMBED_CCOPTS) -o $(BITBUCKET) $(PYTHON_EMBED_LDOPTS) > /dev/null 2>&1 && echo y"), y)
+ifdef NO_LIBPYTHON
 	BASIC_CFLAGS += -DNO_LIBPYTHON
 else
-	ALL_LDFLAGS += $(PYTHON_EMBED_LDOPTS)
-	LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-python.o
-	LIB_OBJS += $(OUTPUT)scripts/python/Perf-Trace-Util/Context.o
+	PYTHON_EMBED_LDOPTS = `python-config --ldflags 2>/dev/null`
+	PYTHON_EMBED_CCOPTS = `python-config --cflags 2>/dev/null`
+	FLAGS_PYTHON_EMBED=$(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS)
+	ifneq ($(call try-cc,$(SOURCE_PYTHON_EMBED),$(FLAGS_PYTHON_EMBED)),y)
+		BASIC_CFLAGS += -DNO_LIBPYTHON
+	else
+		ALL_LDFLAGS += $(PYTHON_EMBED_LDOPTS)
+		LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-python.o
+		LIB_OBJS += $(OUTPUT)scripts/python/Perf-Trace-Util/Context.o
+	endif
 endif
 
 ifdef NO_DEMANGLE
@@ -604,20 +609,23 @@ else ifdef HAVE_CPLUS_DEMANGLE
 	EXTLIBS += -liberty
 	BASIC_CFLAGS += -DHAVE_CPLUS_DEMANGLE
 else
-	has_bfd := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd "$(QUIET_STDERR)" && echo y")
-
+	FLAGS_BFD=$(ALL_CFLAGS) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd
+	has_bfd := $(call try-cc,$(SOURCE_BFD),$(FLAGS_BFD))
 	ifeq ($(has_bfd),y)
 		EXTLIBS += -lbfd
 	else
-		has_bfd_iberty := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty "$(QUIET_STDERR)" && echo y")
+		FLAGS_BFD_IBERTY=$(FLAGS_BFD) -liberty
+		has_bfd_iberty := $(call try-cc,$(SOURCE_BFD),$(FLAGS_BFD_IBERTY))
 		ifeq ($(has_bfd_iberty),y)
 			EXTLIBS += -lbfd -liberty
 		else
-			has_bfd_iberty_z := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty -lz "$(QUIET_STDERR)" && echo y")
+			FLAGS_BFD_IBERTY_Z=$(FLAGS_BFD_IBERTY) -lz
+			has_bfd_iberty_z := $(call try-cc,$(SOURCE_BFD),$(FLAGS_BFD_IBERTY_Z))
 			ifeq ($(has_bfd_iberty_z),y)
 				EXTLIBS += -lbfd -liberty -lz
 			else
-				has_cplus_demangle := $(shell sh -c "(echo 'extern char *cplus_demangle(const char *, int);'; echo 'int main(void) { cplus_demangle(0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -liberty "$(QUIET_STDERR)" && echo y")
+				FLAGS_CPLUS_DEMANGLE=$(ALL_CFLAGS) $(ALL_LDFLAGS) $(EXTLIBS) -liberty
+				has_cplus_demangle := $(call try-cc,$(SOURCE_CPLUS_DEMANGLE),$(FLAGS_CPLUS_DEMANGLE))
 				ifeq ($(has_cplus_demangle),y)
 					EXTLIBS += -liberty
 					BASIC_CFLAGS += -DHAVE_CPLUS_DEMANGLE
@@ -865,7 +873,7 @@ export TAR INSTALL DESTDIR SHELL_PATH
 
 SHELL = $(SHELL_PATH)
 
-all:: .perf.dev.null shell_compatibility_test $(ALL_PROGRAMS) $(BUILT_INS) $(OTHER_PROGRAMS) $(OUTPUT)PERF-BUILD-OPTIONS
+all:: shell_compatibility_test $(ALL_PROGRAMS) $(BUILT_INS) $(OTHER_PROGRAMS) $(OUTPUT)PERF-BUILD-OPTIONS
 ifneq (,$X)
 	$(foreach p,$(patsubst %$X,%,$(filter %$X,$(ALL_PROGRAMS) $(BUILT_INS) perf$X)), test '$p' -ef '$p$X' || $(RM) '$p';)
 endif
@@ -1195,11 +1203,6 @@ clean:
 .PHONY: .FORCE-PERF-VERSION-FILE TAGS tags cscope .FORCE-PERF-CFLAGS
 .PHONY: .FORCE-PERF-BUILD-OPTIONS
 
-.perf.dev.null:
-		touch .perf.dev.null
-
-.INTERMEDIATE:	.perf.dev.null
-
 ### Make sure built-ins do not have dups and listed in perf.c
 #
 check-builtins::

tools/perf/feature-tests.mak

+define SOURCE_HELLO
+#include <stdio.h>
+int main(void)
+{
+	return puts(\"hi\");
+}
+endef
+
+ifndef NO_DWARF
+define SOURCE_DWARF
+#include <dwarf.h>
+#include <libdw.h>
+#include <version.h>
+#ifndef _ELFUTILS_PREREQ
+#error
+#endif
+
+int main(void)
+{
+	Dwarf *dbg = dwarf_begin(0, DWARF_C_READ);
+	return (long)dbg;
+}
+endef
+endif
+
+define SOURCE_LIBELF
+#include <libelf.h>
+
+int main(void)
+{
+	Elf *elf = elf_begin(0, ELF_C_READ, 0);
+	return (long)elf;
+}
+endef
+
+define SOURCE_GLIBC
+#include <gnu/libc-version.h>
+
+int main(void)
+{
+	const char *version = gnu_get_libc_version();
+	return (long)version;
+}
+endef
+
+define SOURCE_ELF_MMAP
+#include <libelf.h>
+int main(void)
+{
+	Elf *elf = elf_begin(0, ELF_C_READ_MMAP, 0);
+	return (long)elf;
+}
+endef
+
+ifndef NO_NEWT
+define SOURCE_NEWT
+#include <newt.h>
+
+int main(void)
+{
+	newtInit();
+	newtCls();
+	return newtFinished();
+}
+endef
+endif
+
+ifndef NO_LIBPERL
+define SOURCE_PERL_EMBED
+#include <EXTERN.h>
+#include <perl.h>
+
+int main(void)
+{
+perl_alloc();
+return 0;
+}
+endef
+endif
+
+ifndef NO_LIBPYTHON
+define SOURCE_PYTHON_EMBED
+#include <Python.h>
+
+int main(void)
+{
+	Py_Initialize();
+	return 0;
+}
+endef
+endif
+
+define SOURCE_BFD
+#include <bfd.h>
+
+int main(void)
+{
+	bfd_demangle(0, 0, 0);
+	return 0;
+}
+endef
+
+define SOURCE_CPLUS_DEMANGLE
+extern char *cplus_demangle(const char *, int);
+
+int main(void)
+{
+	cplus_demangle(0, 0);
+	return 0;
+}
+endef
+
+# try-cc
+# Usage: option = $(call try-cc, source-to-build, cc-options)
+try-cc = $(shell sh -c						  \
+	'TMP="$(TMPOUT).$$$$";			 		  \
+	 echo "$(1)" |						  \
+	 $(CC) -x c - $(2) -o "$$TMP" > /dev/null 2>&1 && echo y; \
+	 rm -f "$$TMP"')