Fix a bug in the IsolateArgumentParser.

Author: christianhaeubl

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/IsolateArgumentParser.java

@@ -192,7 +192,10 @@ public void verifyOptionValues() {
     }
 
     private static boolean shouldValidate(RuntimeOptionKey<?> option) {
-        if (SubstrateOptions.UseSerialGC.getValue()) {
+        if (!option.hasBeenSet()) {
+            /* Workaround for one specific Truffle language that does something weird. */
+            return false;
+        } else if (SubstrateOptions.UseSerialGC.getValue()) {
             /* The serial GC supports changing the heap size at run-time to some degree. */
             return option != SubstrateGCOptions.MinHeapSize && option != SubstrateGCOptions.MaxHeapSize && option != SubstrateGCOptions.MaxNewSize;
         }
@@ -230,12 +233,10 @@ private static Object getOptionValue(int index) {
     }
 
     private static void validate(RuntimeOptionKey<?> option, Object oldValue) {
-        if (option.hasBeenSet()) {
-            Object newValue = option.getValue();
-            if (newValue == null || !newValue.equals(oldValue)) {
-                throw new IllegalArgumentException(
-                                "The option '" + option.getName() + "' can't be changed after isolate creation. Old value: " + oldValue + ", new value: " + newValue);
-            }
+        Object newValue = option.getValue();
+        if (newValue == null || !newValue.equals(oldValue)) {
+            throw new IllegalArgumentException(
+                            "The option '" + option.getName() + "' can't be changed after isolate creation. Old value: " + oldValue + ", new value: " + newValue);
         }
     }
 
@@ -344,6 +345,8 @@ private static boolean atojulong(CCharPointer s, CLongPointer result) {
         }
 
         CCharPointerPointer tailPtr = (CCharPointerPointer) StackValue.get(CCharPointer.class);
+
+        LibC.setErrno(0);
         UnsignedWord n = LibC.strtoull(s, tailPtr, 10);
         if (LibC.errno() != 0) {
             return false;

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/graal/snippets/CEntryPointSnippets.java

@@ -227,13 +227,13 @@ private static int createIsolate(CEntryPointCreateIsolateParameters providedPara
         if (!validPageSize) {
             return CEntryPointErrors.PAGE_SIZE_CHECK_FAILED;
         }
-        CLongPointer parsedArgs = StackValue.get(IsolateArgumentParser.getStructSize());
         CEntryPointCreateIsolateParameters parameters = providedParameters;
         if (parameters.isNull() || parameters.version() < 1) {
             parameters = StackValue.get(CEntryPointCreateIsolateParameters.class);
             parameters.setReservedSpaceSize(WordFactory.zero());
             parameters.setVersion(1);
         }
+        CLongPointer parsedArgs = StackValue.get(IsolateArgumentParser.getStructSize());
         IsolateArgumentParser.parse(parameters, parsedArgs);
         if (parameters.reservedSpaceSize().equal(0)) {
             parameters.setReservedSpaceSize(WordFactory.unsigned(parsedArgs.read(IsolateArgumentParser.getOptionIndex(SubstrateGCOptions.ReservedAddressSpaceSize))));