Arch Linux User Repository

That's only a cycle because your AUR helper doesn't know how to build it. For an AUR helper, build in order: djgpp-djcrx-bootstrap,(djgpp-binutils),djgpp-gcc,djgpp-djcrx. An AUR helper should build djgpp-binutils automatically by djgpp-gcc.

it's been a while and this dependency cycle still exists.

error: can't build djgpp-gcc-12.2.0-2, deps not satisfied: djgpp-djcrx
error: can't build djgpp-djcrx-2.05-11, deps not satisfied: djgpp-gcc
error: packages failed to build: djgpp-gcc-12.2.0-2  djgpp-djcrx-2.05-11

Gforge isn’t just down, it’s gone, summarily killed by INRIA with no official archive available: https://groups.google.com/g/isl-development/c/JGaMo2VUu_8. For now the official source archives for ISL seem to be hosted on Sourceforge, so a minimal fix would be

diff --git a/PKGBUILD b/PKGBUILD
index 9e49a8e..69378db 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -20,7 +20,7 @@ optdepends=('djgpp-djcrx: headers and utilities')
 optdepends+=('djgpp-djcrx-bootstrap: first build of djgpp-gcc before djgpp-djcrx is built')
 options=('!strip' 'staticlibs' '!emptydirs')
 source=("https://ftp.gnu.org/gnu/gcc/gcc-$pkgver/gcc-$pkgver.tar.xz"
-        "http://isl.gforge.inria.fr/isl-${_islver}.tar.bz2"
+        "https://downloads.sourceforge.net/project/libisl/isl-${_islver}.tar.bz2"
         "lto.patch"
        "gcc-djgpp.diff")
 sha256sums=('d08edc536b54c372a1010ff6619dd274c0f1603aa49212ba20f7aa2cda36fa8b'

(don’t forget to also bump pkgrel and update .SRCINFO if applying this as a maintainer!).

options+=('!buildflags')

I managed to make it compile with the following patch:

diff --git a/PKGBUILD b/PKGBUILD
index 9e49a8e..07c8753 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -5,8 +5,7 @@
 pkgname=djgpp-gcc
 pkgver=11.2.0
 _target="i686-pc-msdosdjgpp"
-_islver=0.20
-_djver=2.05
+_islver=0.24
 _build_ada=no
 pkgrel=1
 pkgdesc="GCC for the djgpp cross-compiler"
@@ -14,26 +13,21 @@ arch=('i686' 'x86_64')
 url="http://gcc.gnu.org"
 license=('GPL3' 'LGPL3')
 groups=('djgpp')
-depends=('zlib' 'libmpc' 'djgpp-binutils>=2.30' 'djgpp-djcrx' 'gcc-ada')
+depends=('zlib' 'libmpc' 'djgpp-binutils>=2.30' 'djgpp-djcrx' 'gcc-ada' 'isl')
 makedepends=('unzip')
 optdepends=('djgpp-djcrx: headers and utilities')
 optdepends+=('djgpp-djcrx-bootstrap: first build of djgpp-gcc before djgpp-djcrx is built')
 options=('!strip' 'staticlibs' '!emptydirs')
 source=("https://ftp.gnu.org/gnu/gcc/gcc-$pkgver/gcc-$pkgver.tar.xz"
-        "http://isl.gforge.inria.fr/isl-${_islver}.tar.bz2"
         "lto.patch"
-       "gcc-djgpp.diff")
+        "gcc-djgpp.diff")
 sha256sums=('d08edc536b54c372a1010ff6619dd274c0f1603aa49212ba20f7aa2cda36fa8b'
-            'b587e083eb65a8b394e833dea1744f21af3f0e413a448c17536b5549ae42a4c2'
             'c03dbd61274e1ce14f84366abf348d75779bbd6e0bc32b9f4fd74f1ce54a5ef0'
             '2dfebf23706673e09bffdd367464ccc29e29b5fbcc38885511554430bec4d225')

 prepare() {
   cd gcc-$pkgver

-  # link isl for in-tree build
-  ln -fs "../isl-${_islver}" isl
-
   # build the lto plugin
   patch -Np0 < ../lto.patch

@@ -52,19 +46,24 @@ build() {
      _build_languages=c,c++,fortran,objc,obj-c++
   fi
   if [ "$(gcc -dumpversion | sed -e 's:\..*::')" != "$(echo $pkgver | sed -e 's:\..*::')" ] ; then
-     echo "Different GCC major version: building native compiler at first"
-     mkdir -p gcc-build-native
-     _tmpinst=$(pwd)/gcc-install-native
-     mkdir -p ${_tmpinst}
-     cd gcc-build-native
-     ../gcc-$pkgver/configure --prefix=${_tmpinst} --enable-languages=${_bootstrap_languages} --disable-multilib --enable-__cxa_atexit --disable-plugin --disable-libsanitizer
-     make bootstrap
-     make install
-     cd ..
-     export PATH=${_tmpinst}/bin:$PATH
+    echo "Different GCC major version: building native compiler at first"
+    mkdir -p gcc-build-native
+    _tmpinst=$(pwd)/gcc-install-native
+    mkdir -p ${_tmpinst}
+    cd gcc-build-native
+    ../gcc-$pkgver/configure --prefix=${_tmpinst} --enable-languages=${_bootstrap_languages} \
+      --disable-multilib --enable-__cxa_atexit --disable-plugin --disable-libsanitizer
+    make bootstrap
+    make install
+    cd ..
+    export PATH=${_tmpinst}/bin:$PATH
   fi
+  
   mkdir gcc-build-$_target
   test "$(gcc -dumpversion | sed -e 's:\..*::')" == "$(echo $pkgver | sed -e 's:\..*::')" || exit 1
+  export CFLAGS="$CFLAGS -Wno-error=format-security -fPIC"
+  export CXXFLAGS="$CXXFLAGS -Wno-error=format-security -fPIC"
+  
   cd gcc-build-$_target
   ../gcc-$pkgver/configure --prefix=/usr --libexecdir=/usr/lib \
     --target="$_target" \

This make it dependent on the existing isl AUR package.

URL isl.gforge.inria.fr is still broken, I tried from other locations and clients.

../../../gcc-11.2.0/libcpp/expr.c: In function ‘unsigned int cpp_classify_number(cpp_reader*, const cpp_token*, const char**, location_t)’:
../../../gcc-11.2.0/libcpp/expr.c:811:35: error: format not a string literal and no format arguments [-Werror=format-security]
  811 |             cpp_warning_with_line (pfile, CPP_W_LONG_LONG, virtual_location,
      |             ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  812 |                                    0, message);
      |                                    ~~~~~~~~~~~
../../../gcc-11.2.0/libcpp/expr.c:814:38: error: format not a string literal and no format arguments [-Werror=format-security]
  814 |             cpp_pedwarning_with_line (pfile, CPP_W_LONG_LONG,
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
  815 |                                       virtual_location, 0, message);
      |                                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../../gcc-11.2.0/libcpp/expr.c:824:33: error: format not a string literal and no format arguments [-Werror=format-security]
  824 |           cpp_warning_with_line (pfile, CPP_W_SIZE_T_LITERALS,
      |           ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  825 |                                  virtual_location, 0, message);
      |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1plus: some warnings being treated as errors
make[2]: *** [Makefile:226: expr.o] Error 1
make[2]: Leaving directory '/home/user/.cache/yay/djgpp-gcc/src/gcc-build-i686-pc-msdosdjgpp/build-x86_64-pc-linux-gnu/libcpp'
make[1]: *** [Makefile:2901: all-build-libcpp] Error 2
make[1]: Leaving directory '/home/user/.cache/yay/djgpp-gcc/src/gcc-build-i686-pc-msdosdjgpp'
make: *** [Makefile:959: all] Error 2
==> ERROR: A failure occurred in build().
    Aborting...
 -> error making: djgpp-gcc

Problem downloading sources:

curl: (28) Failed to connect to isl.gforge.inria.fr port 80 after 129355 ms: Connection timed out

Had to disable Ada cross-compiler for gcc-11. libada does not build and I do not know language well enough to try to fix it. I guess one can have alignment related runtime problems with DJGPP programs written also in other languages if program tries to use SSE or AVX

It's is possible to include a gdb build to this package?