Improve template specialisation selection (#1267)

A numeric or boolean template argument in a partial specialisation needs
to be resolved, which isn't currently being handled.

Author: davmac314

core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java

@@ -591,6 +591,26 @@ public void test14_5_4_1s2_MatchingTemplateSpecializations() throws Exception {
 		assertSame(R3.getTemplateDefinition(), A4);
 	}
 
+	// template <typename T> constexpr bool consume_r1() { return true; }
+	// template <class T1, bool EN = true> class A { };
+	// template <class T1> class A <T1, (bool)consume_r1<T1>()> { };
+	// A<int> a1; // uses specialisation
+	public void testPrimitiveMatchingSpecializations() throws Exception {
+		IASTTranslationUnit tu = parse(getAboveComment(), CPP);
+		NameCollector col = new NameCollector();
+		tu.accept(col);
+
+		ICPPClassTemplate A1 = (ICPPClassTemplate) col.getName(4).resolveBinding();
+		ICPPClassTemplate A2 = (ICPPClassTemplate) col.getName(6).resolveBinding();
+
+		assertTrue(A2 instanceof ICPPClassTemplatePartialSpecialization);
+		assertSame(((ICPPClassTemplatePartialSpecialization) A2).getPrimaryClassTemplate(), A1);
+
+		ICPPTemplateInstance R1 = (ICPPTemplateInstance) col.getName(12).resolveBinding();
+
+		assertSame(R1.getTemplateDefinition(), A2);
+	}
+
 	// template <class T> void f(T);
 	// template <class T> void f(T*);
 	// template <> void f(int);       //ok

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java

@@ -877,6 +877,9 @@ private boolean fromTemplateArgument(ICPPTemplateArgument p, ICPPTemplateArgumen
 				}
 			}
 			IValue sval = a.getNonTypeValue();
+			tval = CPPTemplates.instantiateValue(tval, InstantiationContext.forDeduction(fDeducedArgs),
+					IntegralValue.MAX_RECURSION_DEPTH);
+
 			return tval.equals(sval);
 		}