Bug 575702: Nondeterministic makefile ordering (prelude)

This fixes a small and rarely hit in practice regression regarding
nondeterministic ordering in makefile output introduced in 15c29eb (bug
505882).

Multiple values for a build output variable were previously output in
definition order. Now they are generated by iterating over a HashSet,
which does not have a deterministic iteration order. Use a TreeSet for
output in a consistently sorted order instead.

Output variables with multiple values are rare (most tools generate one
output file of a particular type) and this case was not exercised in the
existing unit tests. Modify one such that it does (even if in a somewhat
contrived situation). Of note, ${OUTPUT} cannot be used in the
commandLinePattern for such a tool because it squashes the multiple
values into a single quoted file name - misuse ${FLAGS} instead.

Change-Id: Iaa28525c21d74c87dd4d72a03e334ed0e5576727
Signed-off-by: Christian Walther <walther@indel.ch>

build/org.eclipse.cdt.managedbuilder.core.tests/plugin.xml

@@ -3613,6 +3613,42 @@
 			            outputs="tmp">
 			         </outputType>
 			      </tool>
+			      <tool
+			      		name="touch"
+			      		command="touch"
+			      		commandLinePattern="${COMMAND} -r ${INPUTS} ${FLAGS}"
+			      		id="test30_2.touch">
+					 <optionCategory
+						  name="Options"
+						  id="test30_2.touch.category">
+					 </optionCategory>
+					 <option
+						  name="Touched Files"
+						  category="test30_2.touch.category"
+						  command="&quot;${value}&quot;"
+						  id="test30_2.touch.filenames"
+						  valueType="stringList">
+						<listOptionValue value="these"/>
+						<listOptionValue value="file names"/>
+						<listOptionValue value="are"/>
+						<listOptionValue value="not"/>
+						<listOptionValue value="in"/>
+						<listOptionValue value="alphabetical"/>
+						<listOptionValue value="order"/>
+					 </option>
+			         <inputType
+			            id="test30_2.touch.input1"
+			            buildVariable="LOGFILE"
+			            sources="log">
+			         </inputType>
+			         <outputType
+			            id="test30_2.touch.output"
+			            name="Touched files"
+			            multipleOfType="true"
+			            buildVariable="TOUCHEDFILES"
+			            option="test30_2.touch.filenames">
+			         </outputType>
+			      </tool>
 			  </toolChain>
          </configuration>
       </projectType>                 

build/org.eclipse.cdt.managedbuilder.core.tests/resources/test30Projects/test30_2/Benchmarks/makefile

@@ -32,6 +32,15 @@ new.tar \
 LOGFILE += \
 new.log \
 
+TOUCHEDFILES += \
+alphabetical \
+are \
+file\ names \
+in \
+not \
+order \
+these \
+
 
 # All Target
 all: main-build
@@ -59,9 +68,15 @@ new.log: $(TAROUT) makefile objects.mk $(OPTIONAL_TOOL_DEPS)
 	@echo 'Finished building: $@'
 	@echo ' '
 
+these file\ names are not in alphabetical order: $(LOGFILE) makefile objects.mk $(OPTIONAL_TOOL_DEPS)
+	@echo 'Invoking: touch'
+	touch -r $(LOGFILE) "these" "file names" "are" "not" "in" "alphabetical" "order"
+	@echo 'Finished building: $@'
+	@echo ' '
+
 # Other Targets
 clean:
-	-$(RM) new.log new.tar test30_2.tmp
+	-$(RM) alphabetical are file\ names in new.log new.tar not order test30_2.tmp these
 	-@echo ' '
 
 .PHONY: all clean dependents main-build

build/org.eclipse.cdt.managedbuilder.core.tests/resources/test30Projects/test30_2/Benchmarks/sources.mk

@@ -14,6 +14,7 @@ CC_SRCS :=
 TAROUT := 
 TERMINAL__DUMMY_OUTPUT__OUTPUTS := 
 LOGFILE := 
+TOUCHEDFILES := 
 
 # Every subdirectory with source files must be described here
 SUBDIRS := \

build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/makegen/gnu2/GnuMakefileGenerator.java

@@ -39,6 +39,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
+import java.util.TreeSet;
 import java.util.Vector;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -4035,7 +4036,8 @@ public class GnuMakefileGenerator implements IManagedBuilderMakefileGenerator2 {
 
 					// for projects with specific setting on folders/files do
 					// not clear the macro value on subsequent passes
-					map.putIfAbsent(macroName, new HashSet<>());
+					// use TreeSet for deterministically sorted output
+					map.putIfAbsent(macroName, new TreeSet<>());
 				}
 
 				// Set of input extensions for which macros have been created so far