diff --git a/pkgs/development/compilers/gcc/patches/4.9/darwin-clang-as.patch b/pkgs/development/compilers/gcc/patches/4.9/darwin-clang-as.patch
new file mode 100644
index 000000000000..095713eb6c8c
--- /dev/null
+++ b/pkgs/development/compilers/gcc/patches/4.9/darwin-clang-as.patch
@@ -0,0 +1,16 @@
+diff -ur a/libgcc/config/t-darwin b/libgcc/config/t-darwin
+--- a/libgcc/config/t-darwin	2012-07-14 09:50:59.000000000 -0400
++++ b/libgcc/config/t-darwin	2023-11-05 21:26:11.696825584 -0500
+@@ -7,12 +7,6 @@
+ crttme.o: $(srcdir)/config/darwin-crt-tm.c
+ 	$(crt_compile) $(DARWIN_EXTRA_CRT_BUILD_CFLAGS) -DEND -c $<
+ 
+-# -pipe because there's an assembler bug, 4077127, which causes
+-# it to not properly process the first # directive, causing temporary
+-# file names to appear in stabs, causing the bootstrap to fail.  Using -pipe
+-# works around this by not having any temporary file names.
+-HOST_LIBGCC2_CFLAGS += -pipe
+-
+ # Use unwind-dw2-fde-darwin
+ LIB2ADDEH = $(srcdir)/unwind-dw2.c $(srcdir)/config/unwind-dw2-fde-darwin.c \
+   $(srcdir)/unwind-sjlj.c $(srcdir)/unwind-c.c
diff --git a/pkgs/development/compilers/gcc/patches/default.nix b/pkgs/development/compilers/gcc/patches/default.nix
index 2052d0f674f2..8e295e161869 100644
--- a/pkgs/development/compilers/gcc/patches/default.nix
+++ b/pkgs/development/compilers/gcc/patches/default.nix
@@ -243,6 +243,12 @@ in
   ./6/gnat-glibc234.patch
 ]
 
+# The clang-based assembler used in darwin.cctools-llvm (LLVM >11) does not support piping input.
+# Fortunately, it does not exhibit the problem GCC has with the cctools assembler.
+# This patch can be dropped should darwin.cctools-llvm ever implement support.
+++ optional (!atLeast7 && hostPlatform.isDarwin && lib.versionAtLeast (lib.getVersion stdenv.cc) "12") ./4.9/darwin-clang-as.patch
+
+
 ## gcc 4.9 and older ##############################################################################
 
 ++ optional (!atLeast6) ./parallel-bconfig.patch