Intial experiment for building dynamic images without glibc under pnacl

tests/pnacl_ld_experiments/Makefile

+# Copyright (c) 2012 The Native Client Authors.  All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# simple example(s) for builing shared images with the pnacl TC
+# which do not require glibc
+
+ROOT=$(shell readlink -f ../../)
+TC_ROOT=$(ROOT)/toolchain/pnacl_linux_x86_64/glibc
+PNACL_CC=$(TC_ROOT)/bin/pnacl-clang
+PNACL_LD=$(TC_ROOT)/bin/pnacl-nativeld
+
+BOOTER=$(ROOT)/scons-out/opt-linux-x86-32/staging/nacl_helper_bootstrap
+LOADER=$(ROOT)/scons-out/opt-linux-x86-32/staging/sel_ldr
+LDSO=$(ROOT)/toolchain/pnacl_linux_x86_64/lib-x86-32/runnable-ld.so
+LIBPATH_SHARED=$(ROOT)/toolchain/pnacl_linux_x86_64/lib-x86-32
+PATH_CRT=$(ROOT)/toolchain/pnacl_linux_x86_64/glibc/lib
+PATH_CRT_SRC=$(ROOT)/pnacl/support
+
+COMMON_FLAGS= --pnacl-driver-verbose -save-temps
+
+RUNNER=$(BOOTER) $(LOADER) -S -E LD_DEBUG=all --r_debug=0xXXXXXXXXXXXXXXXX -a \
+       -- $(LDSO) --library-path $(LIBPATH_SHARED)
+
+
+######################################################################
+PNACL_CC_FLAGS = $(COMMON_FLAGS)
+
+hello1.bc:  hello1.c
+        $(PNACL_CC)  -c $(PNACL_CC_FLAGS) -o $@ $^
+
+fortytwo.bc:  fortytwo.c
+        $(PNACL_CC)  -c $(PNACL_CC_FLAGS) -o $@ $^
+
+crtbegin.bc:  $(PATH_CRT_SRC)/crtbegin.c
+        $(PNACL_CC)  -c  $(PNACL_CC_FLAGS) -o $@ $^
+
+crtend.bc:  $(PATH_CRT_SRC)/crtend.c
+        $(PNACL_CC)  -c  $(PNACL_CC_FLAGS) -o $@ $^
+
+# TODO(robertm): add soname and maybe go to pso first
+#libsimple.so: fortytwo.bc
+#       $(PNACL_CC) $(COMMON_FLAGS) -nostdlib -shared -fPIC  -arch x86-32 -o $@ $^
+
+LIBS = -L $(LIBPATH_SHARED)  -l:ld-2.9.so
+LD_FLAGS_NATIVE = --pnacl-allow-native -arch x86-32
+# NOTE: the duplication of crtbegin.bc.
+# The one here was build from $(PATH_CRT_SRC)/bitcode
+# The one above from $(PATH_CRT_SRC)
+INIT = crtbegin.bc $(PATH_CRT)/crt1.bc $(PATH_CRT)/crti.bc  $(PATH_CRT)/crtdummy.bc  $(PATH_CRT)/crtbegin.bc
+
+FINI = crtend.bc
+
+# we run this to steal the .o file
+# the nexe produced by this is unfortunately not a dynamic image
+# because of special handling of -l:ld-2.9.so which gets passed through as
+# --add-extra-dt-needed=ld-nacl-x86-32.so.1 which does not trigger the
+# a dynamic image
+hello1.x86-32.nexe.dummy: hello1.bc crtend.bc crtbegin.bc
+        $(PNACL_CC) $(COMMON_FLAGS) $(LD_FLAGS_NATIVE) -nodefaultlibs -nostdlib \
+        $(INIT) hello1.bc $(LIBS) $(FINI)  -o $@
+
+
+# here we steal the object file from hello1.x86-32.nexe.dummy
+hello1.x86-32.nexe: hello1.x86-32.nexe.dummy
+        $(PNACL_LD) $(COMMON_FLAGS) -arch x86-32   $(LIBS) hello1.x86-32.nexe.dummy---linked.o -o $@

[jvoung - send to chromium..., 2012/05/02 17:27:27]

Actually, so the crtbegin.o and crtend.o mentioned above should really be down
here, right?

[robertm, 2012/05/02 17:33:12]

yes, not sure whether hello1.x86-32.nexe will still build without it, will
explore this in the next CL

On 2012/05/02 17:27:27, jvoung wrote:

+
+
+######################################################################
+
+run1: hello1.x86-32.nexe
+        ${RUNNER}  ./hello1.x86-32.nexe
+
+######################################################################
+
+clean:
+        rm -f *.bc *.o *.ll *.so main *.pso *.raw