[ghactions] Update the doxygen version

.github/workflows/build.yml

@@ -101,12 +101,12 @@ jobs:
         cd $HOME
         git clone https://github.com/doxygen/doxygen.git
         cd doxygen
-        git checkout Release_1_10_0
+        git checkout 0a7e79813
         mkdir build
         cd build
         cmake .. -Duse_libclang=ON -Dstatic_libclang=ON -Duse_libc++=OFF -DLLVM_ROOT=/usr/lib/llvm-15/lib/cmake/llvm -DClang_ROOT=/usr/lib/llvm-15/lib/cmake/clang
         make -j 2 VERBOSE=1
-        make install
+        cp bin/doxygen /usr/local/bin/doxygen
 
     - name: add clang cxxflags
       if: ${{ contains(matrix.cxx, 'clang') }}

doc/ex3.md

@@ -4,16 +4,6 @@
 
 In this example, we show how to use mpi::mpi_type_from_tie, mpi::map_C_function and mpi::map_add to register a new MPI datatype and to define MPI operations for it.
 
-> **Note:** We had to comment the last function parameter in the following two lines in the example code below, otherwise Doxygen would have produced various spurious links:
-> ```cpp
-> auto sum = mpi::reduce(z, world, 0, false, /* mpi::map_add<my_complex>() */);
-> ```
-> and
-> ```cpp
-> auto product = mpi::reduce(z, world, 0, false, /* mpi::map_C_function<my_complex, my_product>() */);
-> ```
-> To run the code, please remove the comments.
-
 ```cpp
 #include <mpi/mpi.hpp>
 #include <iostream>
@@ -46,15 +36,15 @@ int main(int argc, char *argv[]) {
   my_complex z = { world.rank() + 1.0, static_cast<double>(world.rank()) };
 
   // sum z over all processes
-  auto sum = mpi::reduce(z, world, 0, false, /* mpi::map_add<my_complex>() */); // valid C++ code, but doxygen produces spurious links when uncommented
+  auto sum = mpi::reduce(z, world, 0, false, mpi::map_add<my_complex>());
 
   // define a product for my_complex
   auto my_product = [](const my_complex& z1, const my_complex& z2) {
     return my_complex { z1.real * z2.real - z1.imag * z2.imag, z1.real * z2.imag + z1.imag * z2.real };
   };
 
   // multiply z over all processes
-  auto product = mpi::reduce(z, world, 0, false, /* mpi::map_C_function<my_complex, my_product>() */); // valid C++ code, but doxygen produces spurious links when uncommented
+  auto product = mpi::reduce(z, world, 0, false, mpi::map_C_function<my_complex, my_product>());
 
   // print result
   if (world.rank() == 0) {