[BUILD] make it possible to pass alternative arch at build time
When trying to build a 32-bit binary on a 64-bit platform, we generally
need to pass "-m32" to gcc, which is not convenient with current makefile.
Note that this option requires gcc >= 3.
In order to ease parameter passing, a new ARCH= makefile option has been
added. If it receives a target architecture, according "-m32"/"-m64" and
"-march=xxxx" will be passed to gcc. Only the generic makefile has been
changed to support this option right now as the need only appeared on Linux.
The spec file now makes use of this option so that rpmbuild can automatically
build with the proper architecture.
diff --git a/Makefile b/Makefile
index 92aacbf..b8655fb 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
# This GNU Makefile supports different OS and CPU combinations.
#
# You should use it this way :
-# [g]make TARGET=os CPU=cpu USE_xxx=1 ...
+# [g]make TARGET=os ARCH=arch CPU=cpu USE_xxx=1 ...
#
# Valid USE_* options are the following. Most of them are automatically set by
# the TARGET, others have to be explictly specified :
@@ -28,6 +28,7 @@
# Variables useful for packagers :
# CC is set to "gcc" by default and is used for compilation only.
# LD is set to "gcc" by default and is used for linking only.
+# ARCH may be useful to force build of 32-bit binary on 64-bit systems
# CFLAGS is automatically set for the specified CPU and may be overridden.
# LDFLAGS is automatically set to -g and may be overridden.
# SMALL_OPTS may be used to specify some options to shrink memory usage.
@@ -78,6 +79,13 @@
# generic, i586, i686, ultrasparc, custom
CPU = generic
+#### Architecture, used when not building for native architecture
+# Use ARCH=<arch_name> to force build for a specific architecture. Known
+# architectures will lead to "-m32" or "-m64" being added to CFLAGS and
+# LDFLAGS. This can be required to build 32-bit binaries on 64-bit targets.
+# Currently, only x86_64, i386, i486, i586 and i686 are understood.
+ARCH =
+
#### Toolchain options.
# GCC is normally used both for compiling and linking.
CC = gcc
@@ -129,17 +137,25 @@
CPU_CFLAGS.ultrasparc = -O6 -mcpu=v9 -mtune=ultrasparc
CPU_CFLAGS = $(CPU_CFLAGS.$(CPU))
+#### ARCH dependant flags, may be overriden by CPU flags
+ARCH_FLAGS.i386 = -m32 -march=i386
+ARCH_FLAGS.i486 = -m32 -march=i486
+ARCH_FLAGS.i586 = -m32 -march=i586
+ARCH_FLAGS.i686 = -m32 -march=i686
+ARCH_FLAGS.x86_64 = -m64 -march=x86-64
+ARCH_FLAGS = $(ARCH_FLAGS.$(ARCH))
+
#### Common CFLAGS
# These CFLAGS contain general optimization options, CPU-specific optimizations
# and debug flags. They may be overridden by some distributions which prefer to
# set all of them at once instead of playing with the CPU and DEBUG variables.
-CFLAGS = $(CPU_CFLAGS) $(DEBUG_CFLAGS)
+CFLAGS = $(ARCH_FLAGS) $(CPU_CFLAGS) $(DEBUG_CFLAGS)
#### Common LDFLAGS
# These LDFLAGS are used as the first "ld" options, regardless of any library
# path or any other option. They may be changed to add any linker-specific
# option at the beginning of the ld command line.
-LDFLAGS = -g
+LDFLAGS = $(ARCH_FLAGS) -g
#### Target system options
# Depending on the target platform, some options are set, as well as some
@@ -458,6 +474,7 @@
src/haproxy.o: src/haproxy.c
$(CC) $(COPTS) \
-DBUILD_TARGET='"$(strip $(TARGET))"' \
+ -DBUILD_ARCH='"$(strip $(ARCH))"' \
-DBUILD_CPU='"$(strip $(CPU))"' \
-DBUILD_CC='"$(strip $(CC))"' \
-DBUILD_CFLAGS='"$(strip $(VERBOSE_CFLAGS))"' \