Add a "fork" of musl as //fusl.

fusl/tools/musl-gcc.specs.sh

Index: fusl/tools/musl-gcc.specs.sh
diff --git a/fusl/tools/musl-gcc.specs.sh b/fusl/tools/musl-gcc.specs.sh
new file mode 100644
index 0000000000000000000000000000000000000000..294e24f75503be91364dea17c4d0bdbe161c4210
--- /dev/null
+++ b/fusl/tools/musl-gcc.specs.sh
@@ -0,0 +1,37 @@
+incdir=$1
+libdir=$2
+ldso=$3
+cat <<EOF
+%rename cpp_options old_cpp_options
+
+*cpp_options:
+-nostdinc -isystem $incdir -isystem include%s %(old_cpp_options)
+
+*cc1:
+%(cc1_cpu) -nostdinc -isystem $incdir -isystem include%s
+
+*link_libgcc:
+-L$libdir -L .%s
+
+*libgcc:
+libgcc.a%s %:if-exists(libgcc_eh.a%s)
+
+*startfile:
+%{!shared: $libdir/%{pie:S}crt1.o} $libdir/crti.o %{shared|pie:crtbeginS.o%s;:crtbegin.o%s}
+
+*endfile:
+%{shared|pie:crtendS.o%s;:crtend.o%s} $libdir/crtn.o
+
+*link:
+-dynamic-linker $ldso -nostdlib %{shared:-shared} %{static:-static} %{rdynamic:-export-dynamic}
+
+*esp_link:
+
+
+*esp_options:
+
+
+*esp_cpp_options:
+
+
+EOF