diff --git a/include/wx/defs.h b/include/wx/defs.h
index 441baa5571..6cc9f7376a 100644
--- a/include/wx/defs.h
+++ b/include/wx/defs.h
@@ -547,7 +547,7 @@ typedef short int WXTYPE;
     #else
         #define wxDEPRECATED_MSG(msg) __attribute__((deprecated))
     #endif
-#elif wxCHECK_GCC_VERSION(4, 5)
+#elif defined(__GNUC__)
     #define wxDEPRECATED_MSG(msg) __attribute__((deprecated(msg)))
 #elif wxCHECK_VISUALC_VERSION(8)
     #define wxDEPRECATED_MSG(msg) __declspec(deprecated("deprecated: " msg))
@@ -644,7 +644,7 @@ typedef short int WXTYPE;
    Note that these macros apply to both gcc and clang, even though they only
    have "GCC" in their names.
  */
-#if defined(__clang__) || wxCHECK_GCC_VERSION(4, 6)
+#if defined(__clang__) || defined(__GNUC__)
 #   define wxGCC_WARNING_SUPPRESS(x) \
         _Pragma (wxSTRINGIZE(GCC diagnostic push)) \
         _Pragma (wxSTRINGIZE(GCC diagnostic ignored wxSTRINGIZE(wxCONCAT(-W,x))))
diff --git a/include/wx/dlimpexp.h b/include/wx/dlimpexp.h
index fd75cb9d15..a1be764de0 100644
--- a/include/wx/dlimpexp.h
+++ b/include/wx/dlimpexp.h
@@ -25,17 +25,7 @@
 #    if defined(__VISUALC__)
 #        define WXEXPORT __declspec(dllexport)
 #        define WXIMPORT __declspec(dllimport)
-    /*
-        While gcc also supports __declspec(dllexport), it created unusably huge
-        DLL files in gcc 4.[56] (while taking horribly long amounts of time),
-        see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43601. Because of this
-        we rely on binutils auto export/import support which seems to work
-        quite well for 4.5+. However the problem was fixed in 4.7 and later and
-        not exporting everything creates smaller DLLs (~8% size difference), so
-        do use the explicit attributes again for the newer versions.
-     */
-#    elif defined(__GNUC__) && \
-        (!wxCHECK_GCC_VERSION(4, 5) || wxCHECK_GCC_VERSION(4, 7))
+#    elif defined(__GNUC__)
         /*
             __declspec could be used here too but let's use the native
             __attribute__ instead for clarity.
diff --git a/include/wx/platform.h b/include/wx/platform.h
index bc240a33c4..3deb0881cd 100644
--- a/include/wx/platform.h
+++ b/include/wx/platform.h
@@ -578,7 +578,7 @@
 #       if !__has_feature(cxx_rtti)
 #           define wxNO_RTTI
 #       endif
-#   elif wxCHECK_GCC_VERSION(4, 3)
+#   elif defined(__GNUG__)
 #       ifndef __GXX_RTTI
 #           define wxNO_RTTI
 #       endif
diff --git a/include/wx/propgrid/property.h b/include/wx/propgrid/property.h
index b5a89a2dd8..50ebdb8c49 100644
--- a/include/wx/propgrid/property.h
+++ b/include/wx/propgrid/property.h
@@ -454,7 +454,7 @@ wxPG_PROP_CLASS_SPECIFIC_3          = 0x00400000
 // -----------------------------------------------------------------------
 
 // Helpers to mark macros as deprecated
-#if (defined(__clang__) || wxCHECK_GCC_VERSION(4, 5)) && !defined(WXBUILDING)
+#if (defined(__clang__) || defined(__GNUC__)) && !defined(WXBUILDING)
 #define wxPG_STRINGIFY(X) #X
 #define wxPG_DEPRECATED_MACRO_VALUE(value, msg) \
         _Pragma(wxPG_STRINGIFY(GCC warning msg)) value
diff --git a/include/wx/stc/stc.h b/include/wx/stc/stc.h
index e165d730cd..37af238994 100644
--- a/include/wx/stc/stc.h
+++ b/include/wx/stc/stc.h
@@ -2467,7 +2467,7 @@ class WXDLLIMPEXP_FWD_CORE wxScrollBar;
 //----------------------------------------------------------------------
 
 
-#if defined(__clang__) || wxCHECK_GCC_VERSION(4, 5)
+#if defined(__clang__) || defined(__GNUC__)
     #define wxSTC_STRINGIFY(X) #X
     #define wxSTC_DEPRECATED_MACRO_VALUE(value,msg) \
         _Pragma(wxSTC_STRINGIFY(GCC warning msg)) value
diff --git a/src/stc/stc.h.in b/src/stc/stc.h.in
index 6011cf94c9..0dc8e32493 100644
--- a/src/stc/stc.h.in
+++ b/src/stc/stc.h.in
@@ -64,7 +64,7 @@ class WXDLLIMPEXP_FWD_CORE wxScrollBar;
 //----------------------------------------------------------------------
 
 
-#if defined(__clang__) || wxCHECK_GCC_VERSION(4, 5)
+#if defined(__clang__) || defined(__GNUC__)
     #define wxSTC_STRINGIFY(X) #X
     #define wxSTC_DEPRECATED_MACRO_VALUE(value,msg) \
         _Pragma(wxSTC_STRINGIFY(GCC warning msg)) value
diff --git a/tests/allheaders.cpp b/tests/allheaders.cpp
index 12b938b1c3..62a8544f50 100644
--- a/tests/allheaders.cpp
+++ b/tests/allheaders.cpp
@@ -18,7 +18,7 @@
     #define CHECK_GCC_VERSION(major, minor) 0
 #endif
 
-#if CHECK_GCC_VERSION(4, 6) || defined(__clang__)
+#if defined(__GNUC__) || defined(__clang__)
     // As above, we can't reuse wxCONCAT() and wxSTRINGIZE macros from wx/cpp.h
     // here, so define their equivalents here.
     #define CONCAT_HELPER(x, y) x ## y
@@ -32,12 +32,13 @@
     #define WARNING_TURN_OFF(comp, warn) \
         _Pragma(STRINGIZE(comp diagnostic ignored STRINGIZE(CONCAT(-W,warn))))
 
-    #if CHECK_GCC_VERSION(4, 6)
-        #define GCC_TURN_ON(warn) WARNING_TURN_ON(GCC, warn)
-        #define GCC_TURN_OFF(warn) WARNING_TURN_OFF(GCC, warn)
-    #elif defined(__clang__)
+    // Test for clang before gcc as clang defines __GNUC__ too.
+    #if defined(__clang__)
         #define CLANG_TURN_ON(warn) WARNING_TURN_ON(clang, warn)
         #define CLANG_TURN_OFF(warn) WARNING_TURN_OFF(clang, warn)
+    #elif defined(__GNUC__)
+        #define GCC_TURN_ON(warn) WARNING_TURN_ON(GCC, warn)
+        #define GCC_TURN_OFF(warn) WARNING_TURN_OFF(GCC, warn)
     #endif
 #endif
 
@@ -83,9 +84,7 @@
 #if CHECK_GCC_VERSION(6,1)
     GCC_TURN_ON(abi)
 #endif // 6.1
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_ON(abi-tag)
-#endif // 4.8
     GCC_TURN_ON(address)
     GCC_TURN_ON(aggregate-return)
 #if CHECK_GCC_VERSION(7,1)
@@ -124,9 +123,7 @@
 #if CHECK_GCC_VERSION(4,9)
     GCC_TURN_ON(date-time)
 #endif // 4.9
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(delete-non-virtual-dtor)
-#endif // 4.7
 #if CHECK_GCC_VERSION(9,1)
     GCC_TURN_ON(deprecated-copy)
 #endif // 9.1
@@ -156,24 +153,18 @@
 #if CHECK_GCC_VERSION(5,1)
     GCC_TURN_ON(format-signedness)
 #endif // 5.1
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(format-zero-length)
-#endif // 4.7
     GCC_TURN_ON(ignored-qualifiers)
     GCC_TURN_ON(init-self)
     GCC_TURN_ON(inline)
     GCC_TURN_ON(invalid-pch)
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_ON(literal-suffix)
-#endif // 4.8
 #if CHECK_GCC_VERSION(6,1)
     GCC_TURN_ON(logical-op)
 #endif // 6.1
     GCC_TURN_ON(long-long)
     GCC_TURN_ON(main)
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(maybe-uninitialized)
-#endif // 4.7
 #if CHECK_GCC_VERSION(10,1)
     GCC_TURN_ON(mismatched-tags)
 #endif // 10.1
@@ -187,17 +178,13 @@
 #if CHECK_GCC_VERSION(6,1)
     GCC_TURN_ON(namespaces)
 #endif // 6.1
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(narrowing)
-#endif // 4.7
     GCC_TURN_ON(noexcept)
 #if CHECK_GCC_VERSION(7,1)
     GCC_TURN_ON(noexcept-type)
 #endif // 7.1
     GCC_TURN_ON(non-virtual-dtor)
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(nonnull)
-#endif // 4.7
 #if CHECK_GCC_VERSION(6,1)
     GCC_TURN_ON(null-dereference)
 #endif // 6.1
@@ -246,9 +233,7 @@
     GCC_TURN_ON(suggest-attribute=cold)
 #endif // 8.1
     GCC_TURN_ON(suggest-attribute=const)
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_ON(suggest-attribute=format)
-#endif // 4.8
 #if CHECK_GCC_VERSION(8,1)
     GCC_TURN_ON(suggest-attribute=malloc)
 #endif // 8.1
@@ -283,20 +268,14 @@
     GCC_TURN_ON(unused-but-set-variable)
     GCC_TURN_ON(unused-function)
     GCC_TURN_ON(unused-label)
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(unused-local-typedefs)
-#endif // 4.7
     GCC_TURN_ON(unused-macros)
     GCC_TURN_ON(unused-parameter)
     GCC_TURN_ON(unused-value)
     GCC_TURN_ON(unused-variable)
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_ON(useless-cast)
-#endif // 4.8
     GCC_TURN_ON(variadic-macros)
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(vector-operation-performance)
-#endif // 4.7
 #if CHECK_GCC_VERSION(6,1)
     GCC_TURN_ON(virtual-inheritance)
 #endif // 6.1
@@ -306,9 +285,7 @@
 #endif // 10.1
     GCC_TURN_ON(volatile-register-var)
     GCC_TURN_ON(write-strings)
-#if CHECK_GCC_VERSION(4,7)
     GCC_TURN_ON(zero-as-null-pointer-constant)
-#endif // 4.7
     // }}}
 
     #undef GCC_TURN_ON
@@ -324,9 +301,7 @@
     GCC_TURN_OFF(sign-conversion)
 
     GCC_TURN_OFF(old-style-cast)
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_OFF(useless-cast)
-#endif // 4.8
 
 #if CHECK_GCC_VERSION(10,1)
     GCC_TURN_OFF(redundant-tags) // "struct tm" triggers this
@@ -334,7 +309,7 @@
 
     // This one is given for NULL, and not just literal 0, up to gcc 10, and so
     // has to remain disabled for as long as we use any NULLs in our code.
-#if CHECK_GCC_VERSION(4,7) && !CHECK_GCC_VERSION(10,1)
+#if !CHECK_GCC_VERSION(10,1)
     GCC_TURN_OFF(zero-as-null-pointer-constant)
 #endif
 
@@ -356,9 +331,7 @@
 
     // This one is given whenever inheriting from std:: classes without using
     // C++11 ABI tag explicitly, probably harmless.
-#if CHECK_GCC_VERSION(4,8)
     GCC_TURN_OFF(abi-tag)
-#endif // 4.8
 
     // This can be used to ask the compiler to explain why some function is not
     // inlined, but it's perfectly normal for some functions not to be inlined.
diff --git a/tests/log/logtest.cpp b/tests/log/logtest.cpp
index 94d05e737d..75a055b4b7 100644
--- a/tests/log/logtest.cpp
+++ b/tests/log/logtest.cpp
@@ -300,7 +300,7 @@ void LogTestCase::NoWarnings()
 // The following two functions (v, macroCompilabilityTest) are not run by
 // any test, and their purpose is merely to guarantee that the wx(V)LogXXX
 // macros compile without 'dangling else' warnings.
-#if defined(__clang__) || wxCHECK_GCC_VERSION(4, 6)
+#if defined(__clang__) || defined(__GNUC__)
     // gcc 7 split -Wdangling-else from the much older -Wparentheses, so use
     // the new warning if it's available or the old one otherwise.
     #if wxCHECK_GCC_VERSION(7, 0)