Fix MEX compilation on macOS Apple Silicon by forcing classic linker (-ld_classic)

@STL_Formula/private/src/robusthom/CompileRobusthom.m

@@ -25,7 +25,13 @@ function CompileRobusthom()
     ' av_robustness' obj_ext ...
     ];
 
-MEX = 'mex ';
+% Workaround for recent Apple linker on macOS arm64 (maca64):
+% force classic linker for MEX to avoid undefined mex* adapter symbols.
+if ismac && strcmp(computer('arch'),'maca64')
+    MEX = 'mex ''LDFLAGS=\$LDFLAGS -ld_classic'' ';
+else
+    MEX = 'mex ';
+end
 FLAGS = ' ';
 
 if isfield(BreachGlobOpt, 'disable_robust_linear_interpolation')

Core/CompileSystem.m

@@ -117,11 +117,19 @@ function CompileSystem(Sys)
         qwrap([obj_out_dir filesep 'breach' obj_ext ]) ...
         ];
 
+    if ismac && strcmp(computer('arch'),'maca64')
+        % Workaround for recent Apple linker on macOS arm64 (maca64):
+        % force classic linker for MEX to avoid undefined mex* adapter symbols.
+        mex_cmd = 'mex ''LDFLAGS=\$LDFLAGS -ld_classic'' ';
+    else
+        mex_cmd = 'mex ';
+    end
+
     % compile commands
 
-    compile_cvodes_cmd = ['mex -c -outdir ' qwrap(cv_obj_out_dir) ' ' compile_flags ' ' inc_flags ' ' cvodesTB_src_files ];
-    compile_obj_cmd = ['mex -c -outdir ' qwrap(obj_out_dir) ' ' compile_flags ' ' inc_flags ' ' src_files ];
-    compile_cvm_cmd = ['mex -output cvm ' compile_flags obj_files cv_obj_files qwrap(blitz_lib) ];
+    compile_cvodes_cmd = [mex_cmd '-c -outdir ' qwrap(cv_obj_out_dir) ' ' compile_flags ' ' inc_flags ' ' cvodesTB_src_files ];
+    compile_obj_cmd = [mex_cmd '-c -outdir ' qwrap(obj_out_dir) ' ' compile_flags ' ' inc_flags ' ' src_files ];
+    compile_cvm_cmd = [mex_cmd '-output cvm ' compile_flags obj_files cv_obj_files qwrap(blitz_lib) ];
 
     % execute commands
 

Ext/Toolboxes/blitz/CompileBlitzLib.m

@@ -1,6 +1,12 @@
 function CompileBlitzLib()
 
-MEX = 'mex ';
+if ismac && strcmp(computer('arch'),'maca64')
+    % Workaround for recent Apple linker on macOS arm64 (maca64):
+    % force classic linker for MEX to avoid undefined mex* adapter symbols.
+    MEX = 'mex ''LDFLAGS=\$LDFLAGS -ld_classic'' ';
+else
+    MEX = 'mex ';
+end
 INCLUDE = [ '-I.' filesep 'include '];
 FLAGS = ' -c ';
 src_file = ['.' filesep 'src' filesep 'libblitz.cpp '];

Ext/Toolboxes/sundials/sundialsTB/cvodes/cvm/src/setup.m

@@ -5,6 +5,12 @@
 mexopts  = '' ;
 mexflags = '-O' ;
 
+if ismac && strcmp(computer('arch'),'maca64')
+  % Workaround for recent Apple linker on macOS arm64 (maca64):
+  % force classic linker for MEX to avoid undefined mex* adapter symbols.
+  mexflags = sprintf('%s ''LDFLAGS=\$LDFLAGS -ld_classic''', mexflags);
+end
+
 cc          = 'cc' ;
 mpicc       = '' ;
 mpi_incdir  = '' ;

InstallBreach.m

@@ -22,7 +22,13 @@ function InstallBreach(varargin)
 % Johan fix
 silent = 0;
 
-MEX = 'mex ';
+% Workaround for recent Apple linker on macOS arm64 (maca64):
+% force classic linker for MEX to avoid undefined mex* adapter symbols.
+if ismac && strcmp(computer('arch'),'maca64')
+    MEX = 'mex ''LDFLAGS=\$LDFLAGS -ld_classic'' ';
+else
+    MEX = 'mex ';
+end
 FLAGS = ' '; 
 if silent
    FLAGS = [FLAGS ' -silent '];

Online/m_src/compile_stl_mex.m

@@ -70,6 +70,12 @@ function compile_stl_mex(recomp, debug_level)
  cxxflags = '-DIS_PC';
 end    
 
+if ismac && strcmp(computer('arch'),'maca64')
+    % Workaround for recent Apple linker on macOS arm64 (maca64):
+    % force classic linker for MEX to avoid undefined mex* adapter symbols.
+    cxxflags = [cxxflags ' ''LDFLAGS=\$LDFLAGS -ld_classic'' '];
+end
+
 
 if ispc
     obj_ext = 'obj';
@@ -104,4 +110,4 @@ function compile_stl_mex(recomp, debug_level)
     cmd_simulink = sprintf('mex  %s %s %s%s %s -outdir %s', cxxflags, includes,prefix_m,src_s_function , objs, bin_dir);
     eval(cmd_simulink)
 end
-end
+end