Target-specific CFLAGS
Hi, everyone, A couple of weeks back I posted my problems with getting an ancient version of Automake to build two libraries. Each was to use the same source but one should have it's objects compiled with -DFEATURE. I attempted to use the following setup: quote noinst_LIBRARIES = normal.a normal-feature.a normal_a_SOURCES = [bunch of files] normal_feature_a_SOURCES = $(normal_a_SOURCES) normal_feature_a_CFLAGS = -DFEATURE /quote While this didn't work on my old version of Automake, I was told that upgrading to the most recent version (1.8.2) would fix this problem. It doesn't. The second library is compiled using the object files created for the first library. In other words, -DFEATURE is never specified in the compilation of the objects needed for the extra library and I get two copies of the same library (with different names). Where have I gone wrong? Thanks, Scott
RE: Target-specific CFLAGS
From: [EMAIL PROTECTED] quote noinst_LIBRARIES = normal.a normal-feature.a normal_a_SOURCES = [bunch of files] normal_feature_a_SOURCES = $(normal_a_SOURCES) normal_feature_a_CFLAGS = -DFEATURE /quote ... Where have I gone wrong? Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. Sorry for the mails, all. Scott
Re: Target-specific CFLAGS
Drummonds, Scott B [EMAIL PROTECTED] writes: From: [EMAIL PROTECTED] quote noinst_LIBRARIES = normal.a normal-feature.a normal_a_SOURCES = [bunch of files] normal_feature_a_SOURCES = $(normal_a_SOURCES) normal_feature_a_CFLAGS = -DFEATURE /quote ... Where have I gone wrong? Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. You know that CPPFLAGS is for the C preprocessor and CXXFLAGS is for the C++ compiler, right? -- Ben Pfaff email: [EMAIL PROTECTED] web: http://benpfaff.org
RE: Target-specific CFLAGS
I didn't. But I do now. Thanks, Scott -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ben Pfaff Sent: Tuesday, February 24, 2004 1:43 PM To: [EMAIL PROTECTED] Subject: Re: Target-specific CFLAGS Drummonds, Scott B [EMAIL PROTECTED] writes: From: [EMAIL PROTECTED] quote noinst_LIBRARIES = normal.a normal-feature.a normal_a_SOURCES = [bunch of files] normal_feature_a_SOURCES = $(normal_a_SOURCES) normal_feature_a_CFLAGS = -DFEATURE /quote ... Where have I gone wrong? Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. You know that CPPFLAGS is for the C preprocessor and CXXFLAGS is for the C++ compiler, right? -- Ben Pfaff email: [EMAIL PROTECTED] web: http://benpfaff.org
Re: Target-specific CFLAGS
On Tue, 24 Feb 2004, Ben Pfaff wrote: Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. You know that CPPFLAGS is for the C preprocessor and CXXFLAGS is for the C++ compiler, right? This distinction is not entirely correct since CPPFLAGS is normally supplied to the C++ compiler as well. CFLAGS is for the C compiler and CXXFLAGS is for the C++ compiler. Bob == Bob Friesenhahn [EMAIL PROTECTED] http://www.simplesystems.org/users/bfriesen
Re: Target-specific CFLAGS
Bob Friesenhahn [EMAIL PROTECTED] writes: On Tue, 24 Feb 2004, Ben Pfaff wrote: Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. You know that CPPFLAGS is for the C preprocessor and CXXFLAGS is for the C++ compiler, right? This distinction is not entirely correct since CPPFLAGS is normally supplied to the C++ compiler as well. CFLAGS is for the C compiler and CXXFLAGS is for the C++ compiler. Well, yes: C++ uses the C preprocessor. -- Ben Pfaff email: [EMAIL PROTECTED] web: http://benpfaff.org
Re: Target-specific CFLAGS
On Tue, 24 Feb 2004, Ben Pfaff wrote: Bob Friesenhahn [EMAIL PROTECTED] writes: On Tue, 24 Feb 2004, Ben Pfaff wrote: Of course, when my source files are C++ files the _CFLAGS extension does nothing. Changing this to _CPPFLAGS fixed the problem. Duh. You know that CPPFLAGS is for the C preprocessor and CXXFLAGS is for the C++ compiler, right? This distinction is not entirely correct since CPPFLAGS is normally supplied to the C++ compiler as well. CFLAGS is for the C compiler and CXXFLAGS is for the C++ compiler. Well, yes: C++ uses the C preprocessor. Which is not really a great assumption since C++ is a different language and the C++ compiler vendor may not be the same as the C compiler vendor. The behavior of the C++ preprocessing may behave differently. Autoconf and Automake make a lot of assumptions when it comes to C++. Luckily the assumptions are correct more often than not. Bob == Bob Friesenhahn [EMAIL PROTECTED] http://www.simplesystems.org/users/bfriesen
Bug with target specific CFLAGS
Hi, For the GStreamer project (http://www.gstreamer.net/) I've got a Makefile.am which uses target specific CFLAGS, and also has an automake conditional to determine the source files to use. This is generating a functioning makefile, but each of the rules for generating a specific target from a source file appears twice in the makefile, causing make to emit warnings such as: Makefile:1344: warning: overriding commands for target `libgst_la-gstparse.lo' Makefile:966: warning: ignoring old commands for target `libgst_la-gstparse.lo' If the conditional is removed, there is no longer any problem. I've got a minimal example, in the form of a test case, which I attach to this message. PS: thanks for adding the _CFLAGS support: we've had some very nasty hacks in place to do this. We need specific _CFLAGS so that we can specify that -O2 should be used for a particular target rather than -O6: the code is a bit hairy (a cothreads implementation) and -O6 breaks it... We want -O6 elsewhere though. PPS: It would also be helpful if we could add specific flags _after_ the standard CFLAGS - the current implementation adds them before. We need the -O2 to be at the end of the flags line, and I have therefore to clear the default CFLAGS and set specific ones for both of my targets, viz: libcothreads_la_CFLAGS = $(CFLAGS) -O2 libgst_la_CFLAGS = $(CFLAGS) CFLAGS = Being able to do: libcothreads_la_POSTCFLAGS = -O2 would be neater (though the name is bad)... -- Richard #! /bin/sh # Regression test for multiple rules being generated for each target when # conditionals are present. # From Richard Boulton . $srcdir/defs || exit 1 cat configure.in 'END' AC_PROG_CC AM_CONDITIONAL(BAR, true) END cat Makefile.am 'END' if BAR BAR_SRCS = bar.c endif bin_PROGRAMS = foo foo_CFLAGS = -DFOO foo_SOURCES = foo.c END : compile $AUTOMAKE || exit 1 uncondval=`fgrep 'foo-foo.o: foo.c' Makefile.in` cat Makefile.am 'END' foo_SOURCES += $(BAR_SRCS) END $AUTOMAKE || exit 1 condval=`fgrep 'foo-foo.o: foo.c' Makefile.in` test "x$uncondval" == "x$condval"
Re: Bug with target specific CFLAGS
"Richard" == Richard Boulton [EMAIL PROTECTED] writes: Richard Makefile:1344: warning: overriding commands for target Richard `libgst_la-gstparse.lo' Richard Makefile:966: warning: ignoring old commands for target Richard `libgst_la-gstparse.lo' Thanks for the report. Richard I've got a minimal example, in the form of a test case, which Richard I attach to this message. Thanks. I'm checking this in. Richard PPS: It would also be helpful if we could add specific flags Richard _after_ the standard CFLAGS - the current implementation adds Richard them before. We need the -O2 to be at the end of the flags Richard line, and I have therefore to clear the default CFLAGS and Richard set specific ones for both of my targets, viz: For some reason I thought the intent was to let the per-file CFLAGS override the default CFLAGS. But maybe I misremember. Ok, I remember now. CFLAGS is a *user* variable so we have to support it everywhere. AM_CFLAGS is what you should use via configure or whatever. AM_CFLAGS isn't passed to a compilation that has per-target CFLAGS. Tom
