detect and add compiler symbol prefix to the assembly code

Some compiler, such as Blackfin GNU compiler, prefix a charater to any
C symbol in generated assembly code. If any assembly symbol is invoked
from C code, it needs to be prefixed as well.

Note: since autoreconf doesn't work with this package because automake
isn't support

[Ryan: add information about why patching configure is ok]

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Ryan Barnett <rjbarnet@rockwellcollins.com>

--- icu-51.2/source/configure	2014-01-06 17:13:20.907249812 +0800
+++ icu-51.2.bak/source/configure	2014-01-06 17:12:57.335248659 +0800
@@ -612,6 +612,7 @@
 ICUDATA_CHAR
 SAMPLES_TRUE
 TESTS_TRUE
+SYMBOL_PREFIX
 ICULIBSUFFIXCNAME
 U_HAVE_LIB_SUFFIX
 ICULIBSUFFIX
@@ -7226,7 +7227,16 @@
     U_HAVE_LIB_SUFFIX=0
 fi

+# Check compiler generated symbol profix
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for symbol prefix" >&5
+$as_echo "checking for symbol prefix... " >&6; }
+    SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
+                  | ${CPP-${CC-gcc} -E} - 2>&1 \
+                  | ${EGREP-grep} "^PREFIX=" \
+                  | sed -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`

+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $SYMBOL_PREFIX" >&5
+$as_echo "$SYMBOL_PREFIX" >&6; }

 # Enable/disable tests
 # Check whether --enable-tests was given.
--- icu-51.2/source/extra/uconv/Makefile.in	2014-01-06 17:47:13.991347946 +0800
+++ icu-51.2.bak/source/extra/uconv/Makefile.in	2014-01-06 17:48:01.571355282 +0800
@@ -57,7 +57,7 @@
 ## Static mode
 ifeq ($(UCONVMSG_MODE),static)
 DEFS += -DUCONVMSG_LINK=$(MSGNAME)
-UCONVMSG_LIB = $(RESDIR)/$(LIBPREFIX)$(STATIC_PREFIX_WHEN_USED)$(MSGNAME).$(A)
+UCONVMSG_LIB = $(RESDIR)/$(LIBPREFIX)$(STATIC_PREFIX_WHEN_USED)@SYMBOL_PREFIX@$(MSGNAME).$(A)
 LIBS += $(UCONVMSG_LIB)
 PKGMODE=static
 INSTALLTO=$(libdir)
@@ -151,7 +151,7 @@
 endif

 $(UCONVMSG_LIB): $(RESFILES) $(RESDIR)/$(RESDIR).lst pkgdata.inc
-	$(INVOKE) $(PKGDATA_INVOKE_OPTS) $(TOOLBINDIR)/pkgdata -p $(MSGNAME) $(PKGDATA_OPTS) -m $(PKGMODE) -s $(RESDIR) -d $(RESDIR) -T $(RESDIR) $(RESDIR)/$(RESDIR).lst
+	$(INVOKE) $(PKGDATA_INVOKE_OPTS) $(TOOLBINDIR)/pkgdata -p @SYMBOL_PREFIX@$(MSGNAME) $(PKGDATA_OPTS) -m $(PKGMODE) -s $(RESDIR) -d $(RESDIR) -T $(RESDIR) $(RESDIR)/$(RESDIR).lst

 $(RESDIR)/$(RESDIR).lst: Makefile $(srcdir)/resfiles.mk
 	@-$(RMV) $@
--- icu-51.2/source/data/Makefile.in	2014-01-06 19:00:28.879570005 +0800
+++ icu-51.2.bak/source/data/Makefile.in	2014-01-06 19:00:07.891570170 +0800
@@ -175,13 +175,13 @@
 packagedata: icupkg.inc $(PKGDATA_LIST) build-local
 ifneq ($(ENABLE_STATIC),)
 ifeq ($(PKGDATA_MODE),dll)
-	$(PKGDATA_INVOKE) $(PKGDATA) -e $(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBSTATICNAME) -m static $(PKGDATA_VERSIONING) $(PKGDATA_LIST)
+	$(PKGDATA_INVOKE) $(PKGDATA) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBSTATICNAME) -m static $(PKGDATA_VERSIONING) $(PKGDATA_LIST)
 endif
 endif
 ifneq ($(ICUDATA_SOURCE_IS_NATIVE_TARGET),YES)
-	$(PKGDATA_INVOKE) $(PKGDATA) -e $(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) $(PKGDATA_LIBNAME) $(PKGDATA_LIST)
+	$(PKGDATA_INVOKE) $(PKGDATA) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) $(PKGDATA_LIBNAME) $(PKGDATA_LIST)
 ifeq ($(OS390BATCH),1)
-	$(PKGDATA_INVOKE) $(PKGDATA) -e $(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) $(OS390_PDS_NAME) $(PKGDATA_LIST)
+	$(PKGDATA_INVOKE) $(PKGDATA) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -p $(ICUDATA_NAME) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) $(OS390_PDS_NAME) $(PKGDATA_LIST)
 endif
 else
 	$(INSTALL_DATA) $(ICUDATA_SOURCE_ARCHIVE) $(OUTDIR)
@@ -203,11 +203,11 @@
 endif
 ifneq ($(ENABLE_STATIC),)
 ifeq ($(PKGDATA_MODE),dll)
-	$(PKGDATA_INVOKE) $(PKGDATA) -m static -e $(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -s $(BUILDDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBSTATICNAME) $(PKGDATA_LIST) -I $(ICUPKGDATA_INSTALL_LIBDIR)
+	$(PKGDATA_INVOKE) $(PKGDATA) -m static -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -s $(BUILDDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBSTATICNAME) $(PKGDATA_LIST) -I $(ICUPKGDATA_INSTALL_LIBDIR)
 endif
 endif
 ifneq ($(ICUDATA_SOURCE_IS_NATIVE_TARGET),YES)
-	$(PKGDATA_INVOKE) $(PKGDATA) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) -e $(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -s $(BUILDDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBNAME) $(PKGDATA_LIST) -I $(ICUPKGDATA_INSTALL_DIR)
+	$(PKGDATA_INVOKE) $(PKGDATA) -m $(PKGDATA_MODE) $(PKGDATA_VERSIONING) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) -T $(OUTTMPDIR) -s $(BUILDDIR) -p $(ICUDATA_NAME) $(PKGDATA_LIBNAME) $(PKGDATA_LIST) -I $(ICUPKGDATA_INSTALL_DIR)
 else
 	$(INSTALL_DATA) $(ICUDATA_SOURCE_ARCHIVE) $(DESTDIR)$(ICUPKGDATA_DIR)
 endif
@@ -218,7 +218,7 @@
 #### 390 support
 install390: package390
 	$(MKINSTALLDIRS) $(TMPDATADIR) $(DESTDIR)$(libdir)
-	$(INVOKE) $(PKGDATA) -s $(BUILDDIR)$(STUB_SUFFIX) -T $(OUTTMPDIR_390STUB) -p $(ICUDATA_NAME)$(STUB_SUFFIX) $(PKGDATA_LIBNAME)$(STUB_SUFFIX) -e $(ICUDATA_ENTRY_POINT) $(OS390LIST) -m dll $(PKGDATA_VERSIONING) -I $(DESTDIR)$(ICUPKGDATA_DIR)
+	$(INVOKE) $(PKGDATA) -s $(BUILDDIR)$(STUB_SUFFIX) -T $(OUTTMPDIR_390STUB) -p $(ICUDATA_NAME)$(STUB_SUFFIX) $(PKGDATA_LIBNAME)$(STUB_SUFFIX) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) $(OS390LIST) -m dll $(PKGDATA_VERSIONING) -I $(DESTDIR)$(ICUPKGDATA_DIR)
 ifeq ($(PKGDATA_MODE),dll)
 	$(INSTALL-L) $(ICUPKGDATA_OUTDIR)/$(FINAL_IMPORT_LIB) $(DESTDIR)$(ICUPKGDATA_DIR)/$(FINAL_IMPORT_LIB)
 endif
@@ -226,7 +226,7 @@
 #### $(LIB_ICUDATA_NAME)$(STUB_SUFFIX) is the subset data for batch mode
 package390: $(OUTTMPDIR)/icudata390.lst $(PKGDATA_LIST) ./icupkg.inc packagedata
 	ln -s $(ICUDATA_NAME) $(OUTDIR)/build/$(ICUDATA_NAME)$(STUB_SUFFIX)
-	$(INVOKE) $(PKGDATA) -s $(BUILDDIR)$(STUB_SUFFIX) -T $(OUTTMPDIR_390STUB) -p $(ICUDATA_NAME)$(STUB_SUFFIX) $(PKGDATA_LIBNAME)$(STUB_SUFFIX) -e $(ICUDATA_ENTRY_POINT) $(OS390LIST) -m dll $(PKGDATA_VERSIONING)
+	$(INVOKE) $(PKGDATA) -s $(BUILDDIR)$(STUB_SUFFIX) -T $(OUTTMPDIR_390STUB) -p $(ICUDATA_NAME)$(STUB_SUFFIX) $(PKGDATA_LIBNAME)$(STUB_SUFFIX) -e @SYMBOL_PREFIX@$(ICUDATA_ENTRY_POINT) $(OS390LIST) -m dll $(PKGDATA_VERSIONING)
 	cp $(ICUPKGDATA_OUTDIR)/$(LIB_ICUDATA_NAME)$(STUB_SUFFIX).$(SO) $(top_builddir)/stubdata/$(LIB_ICUDATA_NAME)$(STUB_SUFFIX).$(SO)