diff --git a/doc/user_guide/transformations.rst b/doc/user_guide/transformations.rst
index 7fd87a0b41..f41f991468 100644
--- a/doc/user_guide/transformations.rst
+++ b/doc/user_guide/transformations.rst
@@ -344,11 +344,6 @@ can be found in the API-specific sections).
       :members: apply
       :no-index:
 
-.. warning:: This transformation assumes that the MAX Intrinsic acts on
-             PSyIR Real scalar data and does not check that this is
-             not the case. Once issue #658 is on master then this
-             limitation can be fixed.
-
 ####
 
 .. autoclass:: psyclone.psyir.transformations.Maxval2LoopTrans
@@ -361,11 +356,6 @@ can be found in the API-specific sections).
       :members: apply
       :no-index:
 
-.. warning:: This transformation assumes that the MIN Intrinsic acts on
-             PSyIR Real scalar data and does not check that this is
-             not the case. Once issue #658 is on master then this
-             limitation can be fixed.
-
 ####
 
 .. autoclass:: psyclone.psyir.transformations.Minval2LoopTrans
diff --git a/src/psyclone/psyir/transformations/intrinsics/minormax2code_trans.py b/src/psyclone/psyir/transformations/intrinsics/minormax2code_trans.py
index 73aa14bcd6..42b1110e1c 100644
--- a/src/psyclone/psyir/transformations/intrinsics/minormax2code_trans.py
+++ b/src/psyclone/psyir/transformations/intrinsics/minormax2code_trans.py
@@ -47,11 +47,13 @@
 from abc import ABC
 import warnings
 
-from psyclone.psyir.nodes import BinaryOperation, Assignment, \
-        Reference, IfBlock
-from psyclone.psyir.symbols import DataSymbol, REAL_TYPE
-from psyclone.psyir.transformations.intrinsics.intrinsic2code_trans import \
-        Intrinsic2CodeTrans
+from psyclone.psyir.nodes import (
+    BinaryOperation, Assignment, Reference, IfBlock, IntrinsicCall
+)
+from psyclone.psyir.symbols import DataSymbol
+from psyclone.psyir.transformations.intrinsics.intrinsic2code_trans import (
+    Intrinsic2CodeTrans
+)
 from psyclone.utils import transformation_documentation_wrapper
 
 
@@ -85,7 +87,18 @@ def __init__(self):
         super().__init__()
         self._compare_operator = None
 
-    def apply(self, node, options=None, **kwargs):
+    def validate(self, node: IntrinsicCall, options=None, **kwargs):
+        '''
+        Check that it is safe to apply the transformation to the supplied node.
+
+        :param node: the SIGN call to transform.
+        :param options: any of options for the transformation.
+
+        '''
+        super().validate(node, options=options, **kwargs)
+        super()._validate_scalar_arg(node)
+
+    def apply(self, node: IntrinsicCall, options=None, **kwargs):
         '''Apply this utility transformation to the specified node. This node
         must be a MIN or MAX IntrinsicCall. The intrinsic is converted to
         equivalent inline code. This is implemented as a PSyIR transform from:
@@ -117,7 +130,6 @@ def apply(self, node, options=None, **kwargs):
         this is not the case.
 
         :param node: a MIN or MAX intrinsic.
-        :type node: :py:class:`psyclone.psyir.nodes.IntrinsicCall`
         :param options: a dictionary with options for transformations.
         :type options: Optional[Dict[str, Any]]
 
@@ -132,21 +144,14 @@ def apply(self, node, options=None, **kwargs):
         symbol_table = node.scope.symbol_table
         assignment = node.ancestor(Assignment)
 
-        # Create a temporary result variable. There is an assumption
-        # here that the Intrinsic returns a PSyIR real type. This
-        # might not be what is wanted (e.g. the args might PSyIR
-        # integers), or there may be errors (arguments are of
-        # different types) but this can't be checked as we don't have
-        # appropriate methods to query nodes (see #658).
+        # Create two temporary variables.
+        result_type = node.arguments[0].datatype
         res_var_symbol = symbol_table.new_symbol(
             f"res_{self._intrinsic.name.lower()}",
-            symbol_type=DataSymbol, datatype=REAL_TYPE)
-        # Create a temporary variable. Again there is an
-        # assumption here about the datatype - please see previous
-        # comment (associated issue #658).
+            symbol_type=DataSymbol, datatype=result_type)
         tmp_var_symbol = symbol_table.new_symbol(
             f"tmp_{self._intrinsic.name.lower()}",
-            symbol_type=DataSymbol, datatype=REAL_TYPE)
+            symbol_type=DataSymbol, datatype=result_type)
 
         # Replace intrinsic with a temporary (res_var).
         node.replace_with(Reference(res_var_symbol))
diff --git a/src/psyclone/tests/psyir/frontend/fortran_test.py b/src/psyclone/tests/psyir/frontend/fortran_test.py
index 5d873f5e96..150f5d4767 100644
--- a/src/psyclone/tests/psyir/frontend/fortran_test.py
+++ b/src/psyclone/tests/psyir/frontend/fortran_test.py
@@ -38,6 +38,8 @@
 ''' Performs py.test tests on the Fortran PSyIR front-end '''
 
 import pytest
+import sys
+
 from psyclone.configuration import Config
 from psyclone.psyir.frontend.fortran import FortranReader
 from psyclone.psyir.frontend.fparser2 import Fparser2Reader
@@ -97,6 +99,10 @@ def test_fortran_reader_constructor():
     # the return value of this function is tested in the following tests
     freader.psyir_from_source(ONLY_2008_CODE)
 
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     # Now repeat the process with treesitter
     Config.get().frontend = "treesitter"
     freader = FortranReader()
diff --git a/src/psyclone/tests/psyir/frontend/fortran_treesitter_reader/ftr_test.py b/src/psyclone/tests/psyir/frontend/fortran_treesitter_reader/ftr_test.py
index 33705d3033..5b9ba6ebe6 100644
--- a/src/psyclone/tests/psyir/frontend/fortran_treesitter_reader/ftr_test.py
+++ b/src/psyclone/tests/psyir/frontend/fortran_treesitter_reader/ftr_test.py
@@ -38,6 +38,7 @@
 
 import logging
 import pytest
+import sys
 
 from tree_sitter import Node as TSNode
 
@@ -74,6 +75,10 @@ def test_generate_parse_tree(tmpdir_factory, caplog):
     Test that generate_parse_tree returns treesitter trees or appropriate
     error messages.
     '''
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     processor = FortranTreeSitterReader()
 
     # Valid code returns a treesitter Node
@@ -92,7 +97,7 @@ def test_generate_parse_tree(tmpdir_factory, caplog):
     """
     with pytest.raises(ValueError) as err:
         _ = processor.generate_parse_tree_from_source(invalid_code)
-    assert "Syntax Error found at line 2" in str(err.value)
+    assert "Syntax Error found at line" in str(err.value)
 
     # Test providing a source file
     filename = str(tmpdir_factory.mktemp('ts_test').join("testfile.f90"))
@@ -120,6 +125,10 @@ def test_generate_psyir():
     Test that generate_psyir transforms treesitter parse trees to
     PSyIR nodes.
     '''
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     processor = FortranTreeSitterReader()
 
     valid_code = """
@@ -143,6 +152,10 @@ def test_codeblock_generation_and_messages():
     Test that NotImplementedErrors are caught and converted to CodeBlocks
     with the appropriate associated comment
     '''
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     processor = FortranTreeSitterReader()
 
     unsupported_code = """
diff --git a/src/psyclone/tests/psyir/nodes/codeblock_test.py b/src/psyclone/tests/psyir/nodes/codeblock_test.py
index a17f022e4a..2d373180c9 100644
--- a/src/psyclone/tests/psyir/nodes/codeblock_test.py
+++ b/src/psyclone/tests/psyir/nodes/codeblock_test.py
@@ -39,6 +39,8 @@
 ''' Performs py.test tests on the CodeBlock PSyIR node. '''
 
 import pytest
+import sys
+
 from fparser.common.readfortran import FortranStringReader
 from psyclone.configuration import Config
 from psyclone.psyir.frontend.fortran import FortranReader
@@ -65,8 +67,19 @@ def test_codeblock_create():
     assert isinstance(cb, Fparser2CodeBlock)
     assert "a => b" in cb.get_fortran_lines()
 
+    # Use a different fronted value
+    Config.get()._frontend = "newfrontend"
+    with pytest.raises(InternalError) as err:
+        cb = CodeBlock.create("3 + 3", partial_code="expression")
+    assert ("The 'newfrontend' frontend does not have an associated CodeBlock "
+            "subclass" in str(err.value))
+
     # Use the treesitter frontend (the frontend doesn't support partial
     # expressions yet, but it gets an appropriate error)
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     Config.get()._frontend = "treesitter"
     cb = CodeBlock.create("program test\nend program\n")
     assert isinstance(cb, TreeSitterCodeBlock)
@@ -77,13 +90,6 @@ def test_codeblock_create():
         cb = CodeBlock.create("a => b", partial_code="pointer_assignment")
     assert "Syntax Error found at line 1: a => b" in str(err.value)
 
-    # Use a different fronted value
-    Config.get()._frontend = "newfrontend"
-    with pytest.raises(InternalError) as err:
-        cb = CodeBlock.create("3 + 3", partial_code="expression")
-    assert ("The 'newfrontend' frontend does not have an associated CodeBlock "
-            "subclass" in str(err.value))
-
 
 def test_codeblock_node_str():
     ''' Check the node_str method of the Code Block class.'''
@@ -184,6 +190,10 @@ def test_codeblock_get_fortran_lines():
     assert "subroutine mytest" in block.get_fortran_lines()
     assert "end subroutine" in block.get_fortran_lines()
 
+    # TODO #3416: Skip treesitter tests below 3.10 as they're unsupported by
+    # treesitter.
+    if sys.version_info < (3, 10):
+        return
     tree = FortranTreeSitterReader().generate_parse_tree_from_source(code)
     block = TreeSitterCodeBlock(tree, CodeBlock.Structure.STATEMENT)
     assert isinstance(block.get_fortran_lines(), list)
diff --git a/src/psyclone/tests/psyir/transformations/intrinsics/max2code_trans_test.py b/src/psyclone/tests/psyir/transformations/intrinsics/max2code_trans_test.py
index b2dea24fac..38f07a3769 100644
--- a/src/psyclone/tests/psyir/transformations/intrinsics/max2code_trans_test.py
+++ b/src/psyclone/tests/psyir/transformations/intrinsics/max2code_trans_test.py
@@ -69,8 +69,8 @@ def test_apply(fortran_reader, fortran_writer):
   integer :: j
   integer :: k
   integer :: l
-  real :: res_max
-  real :: tmp_max
+  integer :: res_max
+  integer :: tmp_max
 
   res_max = i
   tmp_max = j
diff --git a/src/psyclone/tests/psyir/transformations/intrinsics/min2code_trans_test.py b/src/psyclone/tests/psyir/transformations/intrinsics/min2code_trans_test.py
index 82bd85d7a2..bfc2fd90e3 100644
--- a/src/psyclone/tests/psyir/transformations/intrinsics/min2code_trans_test.py
+++ b/src/psyclone/tests/psyir/transformations/intrinsics/min2code_trans_test.py
@@ -70,8 +70,8 @@ def test_apply(fortran_reader, fortran_writer):
   integer :: j
   integer :: k
   integer :: l
-  real :: res_min
-  real :: tmp_min
+  integer :: res_min
+  integer :: tmp_min
 
   res_min = i
   tmp_min = j