diff --git a/pkgs/development/compilers/gcc/default.nix b/pkgs/development/compilers/gcc/default.nix
index 57141ba23e2e..628b259acbd9 100644
--- a/pkgs/development/compilers/gcc/default.nix
+++ b/pkgs/development/compilers/gcc/default.nix
@@ -392,7 +392,11 @@ lib.pipe ((callFile ./common/builder.nix {}) ({
       EXTRA_LDFLAGS_FOR_TARGET
       ;
   } // optionalAttrs is7 {
-    NIX_CFLAGS_COMPILE = lib.optionalString (stdenv.cc.isClang && langFortran) "-Wno-unused-command-line-argument";
+    NIX_CFLAGS_COMPILE = lib.optionalString (stdenv.cc.isClang && langFortran) "-Wno-unused-command-line-argument"
+      # Downgrade register storage class specifier errors to warnings when building a cross compiler from a clang stdenv.
+      + lib.optionalString (stdenv.cc.isClang && targetPlatform != hostPlatform) " -Wno-register";
+  } // optionalAttrs (!is7 && !atLeast12 && stdenv.cc.isClang && targetPlatform != hostPlatform) {
+    NIX_CFLAGS_COMPILE = "-Wno-register";
   } // optionalAttrs (!atLeast7) {
     inherit langJava;
   } // optionalAttrs atLeast6 {
@@ -420,8 +424,10 @@ lib.pipe ((callFile ./common/builder.nix {}) ({
     ;
   } // lib.optionalAttrs (!atLeast11) {
     badPlatforms = if !(is48 || is49) then [ "aarch64-darwin" ] else lib.platforms.darwin;
+  } // lib.optionalAttrs is11 {
+    badPlatforms = if targetPlatform != hostPlatform then [ "aarch64-darwin" ] else [ ];
   };
-} // lib.optionalAttrs (!atLeast10 && stdenv.hostPlatform.isDarwin) {
+} // lib.optionalAttrs (!atLeast10 && stdenv.targetPlatform.isDarwin) {
   # GCC <10 requires default cctools `strip` instead of `llvm-strip` used by Darwin bintools.
   preBuild = ''
     makeFlagsArray+=('STRIP=${lib.getBin darwin.cctools-port}/bin/${stdenv.cc.targetPrefix}strip')
diff --git a/pkgs/development/compilers/gcc/patches/11/avr-gcc-11.3-darwin.patch b/pkgs/development/compilers/gcc/patches/11/avr-gcc-11.3-darwin.patch
deleted file mode 100644
index 787862fbcffa..000000000000
--- a/pkgs/development/compilers/gcc/patches/11/avr-gcc-11.3-darwin.patch
+++ /dev/null
@@ -1,20 +0,0 @@
---- a/gcc/config/avr/avr.c	2022-10-08 19:18:33.000000000 +0200
-+++ b/gcc/config/avr/avr.patched.c	2022-10-08 19:19:34.000000000 +0200
-@@ -10196,7 +10196,7 @@
-    to track need of __do_copy_data.  */
- 
- static void
--avr_output_data_section_asm_op (const void *data)
-+avr_output_data_section_asm_op (const char *data)
- {
-   avr_need_copy_data_p = true;
- 
-@@ -10209,7 +10209,7 @@
-    to track need of __do_clear_bss.  */
- 
- static void
--avr_output_bss_section_asm_op (const void *data)
-+avr_output_bss_section_asm_op (const char *data)
- {
-   avr_need_clear_bss_p = true;
- 
diff --git a/pkgs/development/compilers/gcc/patches/default.nix b/pkgs/development/compilers/gcc/patches/default.nix
index 9eda241f6d3a..32938be376d9 100644
--- a/pkgs/development/compilers/gcc/patches/default.nix
+++ b/pkgs/development/compilers/gcc/patches/default.nix
@@ -175,9 +175,6 @@ in
 
 ## gcc 11.0 and older ##############################################################################
 
-# https://github.com/osx-cross/homebrew-avr/issues/280#issuecomment-1272381808
-++ optional (is11 && stdenv.isDarwin && targetPlatform.isAvr) ./avr-gcc-11.3-darwin.patch
-
 # libgcc’s `configure` script misdetects aarch64-darwin, resulting in an invalid deployment target.
 ++ optional (is11 && stdenv.isDarwin && stdenv.isAarch64) ./11/libgcc-aarch64-darwin-detection.patch