From 01a11b2dd984b2e32bdc7da101c6971a22f31eea Mon Sep 17 00:00:00 2001 From: "ol.sc" Date: Mon, 28 Sep 2009 21:55:51 +0000 Subject: [PATCH] Added documentation on using GNU Make for building cc65 projects. git-svn-id: svn://svn.cc65.org/cc65/trunk@4263 b7a2c559-68d2-44c3-8de9-860c34a00d81 --- doc/Makefile | 1 + doc/index.sgml | 3 + doc/make.sgml | 169 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 173 insertions(+) create mode 100644 doc/make.sgml diff --git a/doc/Makefile b/doc/Makefile index c3c5d481e..0ebe6b970 100644 --- a/doc/Makefile +++ b/doc/Makefile @@ -43,6 +43,7 @@ SGML = apple2.sgml \ ld65.sgml \ library.sgml \ lynx.sgml \ + make.sgml \ nes.sgml \ pet.sgml \ plus4.sgml \ diff --git a/doc/index.sgml b/doc/index.sgml index 1cef7a63d..5e4bff038 100644 --- a/doc/index.sgml +++ b/doc/index.sgml @@ -62,6 +62,9 @@ Main documentation page, contains links to other available stuff. How to compile cc65 and the support tools. + + Build programs, using the GNU Make utility. + Debug programs, using the VICE emulator. diff --git a/doc/make.sgml b/doc/make.sgml new file mode 100644 index 000000000..3efc76aae --- /dev/null +++ b/doc/make.sgml @@ -0,0 +1,169 @@ + + +
+ +Using GNU Make with cc65 +<author>Oliver Schmidt, <htmlurl url="mailto:ol.sc@web.de" name="ol.sc@web.de"> +<date>26.06.2009 + +<abstract> +How to build your program using the GNU Make utility. +</abstract> + +<!-- Table of contents --> +<toc> + +<!-- Begin the document --> + +<sect>Overview<p> + +This document describes how to build your programs using the cc65 development +tools and the GNU Make utility. + +The cc65 development package doesn't come with a make utility. However this is +no issue because GNU Make works very nicely with cc65. + + + +<sect>What is GNU Make?<p> + +GNU Make is a both very powerful and very popular make utility. It might even +be called the de facto standard for make utilities. For more information see +the GNU Make home page: + +<url url="http://www.gnu.org/software/make/"> + +The cc65 development package is available as binaries for several host systems +and can easily built for quite some additional systems. The very same is true +for GNU Make so a cc65-based project coming with a GNU Make Makefile can easily +be built by any cc65 developer no matter what host system is used. + +Because of the strong alignment of the cc65 compiler with the ISO C standard it +is very well feasable to compile a single C code base both with the cc65 +compiler and other C compilers like for example GCC. GNU Make turns out to be +very well suited to build projects for several target systems using multiple +compilers as it isn't tied to any C compiler. + + + +<sect>A sample Makefile<p> + +This Makefile is a fully functional sample for compiling several C sources +(here <tt/foo.c/ and <tt/bar.c/) and link the resulting object files into an +executable program (here <tt/foobar/): + +<tscreen><verb> +SOURCES = foo.c bar.c + +PROGRAM = foobar + +ifdef CC65_TARGET +CC = $(CC65_HOME)/bin/cl65 +CFLAGS = -t $(CC65_TARGET) --create-dep -O +LDFLAGS = -t $(CC65_TARGET) -m $(PROGRAM).map +else +CC = gcc +CFLAGS = -MMD -MP -O +LDFLAGS = -Wl,-Map,$(PROGRAM).map +endif + +######################################## + +ifdef CC65_TARGET +define MAKEDEPEND +sed -e"s!.s:!.o:!p" -e"s![^\t]*\t\(.*\)!\1:!" < $(<:.c=.u) > $(@:.o=.d) +rm -f $(<:.c=.u) +endef +endif + +.SUFFIXES: +.PHONY: all +all: $(PROGRAM) + +ifneq ($(MAKECMDGOALS),clean) +-include $(SOURCES:.c=.d) +endif + +clean: + rm -f $(SOURCES:.c=.o) $(SOURCES:.c=.d) $(PROGRAM) $(PROGRAM).map + +%.o: %.c + $(CC) -c $(CFLAGS) $< -o $@ + @$(MAKEDEPEND) + +$(PROGRAM): $(SOURCES:.c=.o) + $(CC) $(LDFLAGS) $^ -o $@ +</verb></tscreen> + + +<sect1>Invoking the sample Makefile<p> + +Without any specific configuration the sample Makefile will compile and link +using GCC. In order to rather use cc65 the variable <tt/CC65_TARGET/ needs to be +defined. This may by done as an environment variable or simply as part of the +Makefile. However to quickly switch between compilers and/or cc65 targets it is +best done on the GNU Make command line like this: + +<tscreen><verb> +make CC65_TARGET=c64 +</verb></tscreen> + +The sample Makefile doesn't require cc65 to be "installed" in any way. Rather it +only presumes the single variable <tt/CC65_HOME/ to point to the directory the +cc65 packages were unpacked into. Again there are several ways to define this +variable but as its value typically won't change often it is best done as an +environment variable. + + +<sect1>Understanding the sample Makefile<p> + +Most parts of the sample Makefile follow the guidlines in the +<htmlurl url="http://www.gnu.org/software/make/manual/make.html" name="GNU Make Manual"> +that can be searched online for background information. The automatic generation of +dependency however rather works as described by the GNU Make maintainer Paul D. Smith in +<htmlurl url="http://make.paulandlesley.org/autodep.html#advanced" name="Advanced Auto-Dependencies">. + +In the meantime GCC supports this method directly with the preprocessor option +<tt/-MP/ while cc65 requires some post-processing of the dependency file with +<tt/sed/ adding a second line like in this example: + +<tscreen><verb> +foo.o: foo.c foo.h bar.h +foo.c foo.h bar.h: +</verb></tscreen> + + +<sect1>Invoking the sample Makefile on Windows<p> + +The recommended way to use GNU Make on Windows is to install it as part of a +Cygwin environment. For more information see the Cygwin home page: + +<url url="http://www.cygwin.com/"> + +If however installing Cygwin shouldn't be an option for one or the other reason +then the sample Makefile may be invoked from the Windows Command Prompt (cmd.exe) +by downloading the following programs: + +<itemize> +<item>make.exe: <url url="http://gnuwin32.sourceforge.net/packages/make.htm"> +<item>sed.exe: <url url="http://gnuwin32.sourceforge.net/packages/sed.htm"> +<item>rm.exe: <url url="http://gnuwin32.sourceforge.net/packages/coreutils.htm"> +</itemize> + + + +<sect>Target-specific Variable Values<p> + +The very limited resources of the cc65 target machines now and then require +manual optimization of the build process by compiling individual source files +with different compiler options. GNU Make offers +<htmlurl url="http://www.gnu.org/software/make/manual/html_node/Target_002dspecific.html" name="Target-specific Variable Values"> +perfectly suited for doing so. For example placing the code of the two modules +<tt/foo/ and <tt/bar/ in the segment <tt/FOOBAR/ can be archived with this +target-specific variable definition: + +<tscreen><verb> +foo.o bar.o: CFLAGS += --code-name FOOBAR +</verb></tscreen> + +</article> -- 2.39.5