ICU-20978 Reduce unnecessary building for tools when cross-building

icu4c/source/Makefile.in

@@ -38,7 +38,7 @@ subdir = .
 @TOOLS_TRUE@@TESTS_TRUE@TEST = test
 @SAMPLES_TRUE@SAMPLE = samples
 @TOOLS_TRUE@TOOLS = tools
-@TOOLS_TRUE@DATASUBDIR = data
+@DATA_TRUE@DATASUBDIR = data
 
 ## pkgconfig setup. Always have uc and i18n. Others are optional.
 ALL_PKGCONFIG_SUFFIX=uc i18n

icu4c/source/configure

@@ -645,6 +645,8 @@ ICULIBSUFFIX
 DATA_PACKAGING_MODE
 thepkgicudatadir
 pkgicudatadir
+U_HAVE_DATA
+DATA_TRUE
 U_HAVE_FUZZER
 FUZZER_TRUE
 U_HAVE_TOOLS
@@ -7769,6 +7771,16 @@ else
 fi
 
 
+
+if test "$tools" = true || test "$cross_compiling" = "yes"; then
+  DATA_TRUE=
+  U_HAVE_DATA=1
+else
+  DATA_TRUE='#'
+  U_HAVE_DATA=0
+fi
+
+
 # Check whether --with-data-packaging was given.
 if test "${with_data_packaging+set}" = set; then :
   withval=$with_data_packaging; case "${withval}" in

icu4c/source/configure.ac

@@ -1143,6 +1143,8 @@ AC_ARG_ENABLE(fuzzer,
 	fuzzer=false)
 ICU_CONDITIONAL(FUZZER, test "$fuzzer" = true)
 
+ICU_CONDITIONAL(DATA, test "$tools" = true || test "$cross_compiling" = "yes")
+
 AC_ARG_WITH(data-packaging,
 	[  --with-data-packaging     specify how to package ICU data. Possible values:
         files    raw files (.res, etc)