racket: add support for musl

Closes: #12721
Signed-off-by: Jürgen Buchmüller <pullmoll@t-online.de>

srcpkgs/racket/patches/musl-fixes.patch

@@ -0,0 +1,26 @@
+This patch fixes error:
+
+    env XFORM_USE_PRECOMP=xsrc/precomp.h ../racketcgc  -cqu ./xform.rkt --setup . --depends --cpp "gcc -E -I./.. -I./../include -I./../../rktio -I../../rktio -Os -fomit-frame-pointer -pthread  -DUSE_SENORA_GC   -DMZ_USES_SHARED_LIB "  --keep-lines -o xsrc/future.c ./../src/future.c
+    Error [GCING] 234 in ./../src/bool.c: Function mz_long_double_eqv declared __xform_nongcing__, but includes a function call at __FLOAT_BITS.
+    Error [GCING] 270 in ./../src/bool.c: Function double_eqv declared __xform_nongcing__, but includes a function call at __FLOAT_BITS.
+    xform: Errors converting
+      context...:
+       src/racket/gc2/xform-collects/compiler/priva...:8:2: xform
+       src/racket/gc2/xform-collects/xform/xform-mo...: [running body]
+       src/racket/gc2/xform.rkt: [running body]
+
+Resources:
+  * https://github.com/racket/racket/issues/1638
+  * https://github.com/NixOS/nixpkgs/pull/31017
+  * https://github.com/racket/racket/pull/1886
+
+--- collects/compiler/private/xform.rkt
+--- collects/compiler/private/xform.rkt
+@@ -924,6 +924,7 @@
+                |GetStdHandle| |__CFStringMakeConstantString|
+                _vswprintf_c
+ 	       malloc strdup
++	       __FLOAT_BITS __DOUBLE_BITS ; musl
+                
+                scheme_make_small_bignum scheme_make_small_rational scheme_make_small_complex))
+         (define non-functions-table

srcpkgs/racket/template

@@ -1,7 +1,7 @@
 # Template file for 'racket'
 pkgname=racket
 version=6.12
-revision=1
+revision=2
 build_style=gnu-configure
 build_wrksrc=src
 hostmakedepends="gsfonts"
@@ -14,22 +14,27 @@ homepage="http://racket-lang.org/"
 distfiles="http://mirror.racket-lang.org/installers/$version/$pkgname-$version-src.tgz"
 checksum=655e052847c53e7c64ab9ad2247860c7b9abe2c4b0966474f0375127fff58c33
 nostrip=yes
-only_for_archs="i686 x86_64 armv5tel armv6l armv7l aarch64"
+configure_args="--disable-docs"
 
 if [ "$CROSS_BUILD" ]; then
 	configure_args+=" --enable-racket=/usr/bin/racket"
 	hostmakedepends+=" racket"
 fi
 
+case "$XBPS_TARGET_MACHINE" in
+*-musl)
+	makedepends+=" libucontext-devel";;
+esac
+
+pre_configure() {
+	case "$XBPS_TARGET_MACHINE" in
+	*-musl)
+		export CFLAGS+=" -D_GNU_SOURCE"
+		export LIBS+=" -lucontext"
+		;;
+	esac
+}
+
 post_install() {
 	vlicense COPYING-libscheme.txt
 }
-
-racket-doc_package() {
-	noarch=yes
-	short_desc+=" -- documentation"
-	depends="racket>=${version}_${revision}"
-	pkg_install() {
-		vmove usr/share/doc/racket
-	}
-}