new mingw example (#3717)

* new mingw example

* Update examples/dev_flow/tool_requires/mingw.rst

---------

Co-authored-by: Carlos Zoido <mrgalleta@gmail.com>

Author: memsharded

examples/dev_flow.rst

@@ -8,3 +8,4 @@ Developer tools and flows
 
    dev_flow/debug/step_into_dependencies
    dev_flow/debug/debugging_visual
+   dev_flow/tool_requires/mingw

examples/dev_flow/tool_requires/mingw.rst

@@ -0,0 +1,83 @@
+.. _examples_dev_flow_tool_requires_mingw:
+
+Using a MinGW as tool_requires to build with gcc in Windows
+-----------------------------------------------------------
+
+If we had MinGW installed in our environment, we could define a profile like:
+
+.. code-block::
+
+    [settings]
+    os=Windows
+    compiler=gcc
+    compiler.version=12
+    compiler.libcxx=libstdc++11
+    compiler.threads=posix
+    compiler.exception=sjlj
+    arch=x86_64
+    build_type=Release
+
+    [buildenv]
+    PATH+=(path)C:/path/to/mingw/bin
+    # other environment we might need like
+    CXX=C:/path/to/mingw/bin/g++
+    # etc
+
+    [conf]
+    # some configuration like 'tools.build:compiler_executables' might be needed for some cases
+
+
+But we can also use a Conan package that contains a copy of the MinGW compiler and use it
+as a ``tool_requires`` instead:
+
+.. code-block::
+    :caption: mingw-profile.txt
+
+    [settings]
+    os=Windows
+    compiler=gcc
+    compiler.version=12
+    compiler.libcxx=libstdc++11
+    compiler.threads=posix
+    compiler.exception=seh
+    arch=x86_64
+    build_type=Release
+
+
+    [tool_requires]
+    mingw-builds/12.2.0
+
+
+With this profile we can for example create a package in Windows with:
+
+
+.. code-block:: bash
+
+    # Using a basic template project
+    $ conan new cmake_lib -d name=mypkg -d version=0.1
+    $ conan create . -pr=mingw
+    ...
+    -- The CXX compiler identification is GNU 12.2.0
+    ...
+
+
+    ======== Testing the package: Executing test ========
+    mypkg/0.1 (test package): Running test()
+    mypkg/0.1 (test package): RUN: .\example
+    mypkg/0.1: Hello World Release!
+    mypkg/0.1: _M_X64 defined
+    mypkg/0.1: __x86_64__ defined
+    mypkg/0.1: _GLIBCXX_USE_CXX11_ABI 1
+    mypkg/0.1: MSVC runtime: MultiThreadedDLL
+    mypkg/0.1: __cplusplus201703
+    mypkg/0.1: __GNUC__12
+    mypkg/0.1: __GNUC_MINOR__2
+    mypkg/0.1: __MINGW32__1
+    mypkg/0.1: __MINGW64__1
+    mypkg/0.1 test_package
+
+
+.. seealso::
+
+    - The ConanCenter web page for the `mingw-builds package <https://conan.io/center/recipes/mingw-builds>`_
+    - The ``conan-center-index`` `mingw-builds Github repo recipe <https://github.com/conan-io/conan-center-index/tree/master/recipes/mingw-builds/all>`_

tutorial/consuming_packages/use_tools_as_conan_packages.rst

@@ -239,6 +239,6 @@ the environment activation:
     - :ref:`Using [system_tools] in your profiles <reference_config_files_profiles_system_tools>`.
     - :ref:`Creating recipes for tool_requires: packaging build tools <tutorial_other_tool_requires_packages>`.
     - :ref:`examples_graph_tool_requires_protobuf`
-    - Using MinGW as tool_requires
+    - :ref:`examples_dev_flow_tool_requires_mingw`
     - :ref:`Using tool_requires in profiles <reference_config_files_profile_patterns>`
     - Using conf to set a toolchain from a tool requires