ERC throws no error with connected power pins

[Bernd Wiebus]

Hello

There is an issue with power symbols/flags
If i connect +5V, PWR_FLAG and GNDREF direct, as an example, and i run an ERC with default settings, i get NO Error, but i should get an error, at least a Warning.
This is done with the default settings of the ERC Matrix.
Of course, if i put a power flag to the different voltages separatly, i get an error message if i connect #5V and GNDREF direct. But not at the point where the error happens, but somewhere at the declaration, which is also nasty. But of course, better a strange hint than nothing at all.

The same happens, if i connect +5V, +12V, PWR_FLAG and GNDREF direct.

I think somehow there should be a check that there is only one label attached to a net. In my opinion it is not good to name a net with different labels. If i want to tie different labels, as an example analog ground and digital ground, it should be done with a sort of "net tie". (But this will rise another issues with copper in footprints and DRC at PCBnew) So at least a warning should be thrown.

It happens for me with an older version of KiCad: 5.0.2+dfsg1-1, release build, (details further below) but some discussions show me, that the problem will exist in newer versions also.

Link to this discussion (german, sorry):
https://www.mikrocontroller.net/topic/484055#new

A partly solve of the Problem would be, to change the ERC matrix, to get an error or warning, if power inputs are connected. But this is not default.
Also this would not help in cases were you accidentaly connect two or more different labeled nets. Here you have to look, wether there are different labels at one and the same net.

At the attachmend you fill find a zip file called "KiCad_ERC-Error_14Nov2019.zip" with a KiCad Projekt "Test1" which contains the bad schematic, a picture "Picture_BadSchematic_Test1_24Nov2019.png" with the bad schematic and a picture "Picture_ERC-Defaults_Test1_14Nov2019.png" of the dafault ERC matrix.

And now the version in detail:

Application: kicad
Version: 5.0.2+dfsg1-1, release build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.0 OpenSSL/1.1.1d zlib/1.2.11 libidn2/2.0.5 libpsl/0.20.2 (+libidn2/2.0.5) libssh2/1.8.0 nghttp2/1.36.0 librtmp/2.3
Platform: Linux 4.19.0-6-686-pae i686, 32 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 2.24
    Boost: 1.67.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.62.0
    Compiler: GCC 8.2.0 with C++ ABI 1013

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_WXPYTHON=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON

With best regards: Bernd Wiebus alias dl1eic

[Michael Kavanagh (michaelkavanagh)]

Please upgrade to the latest stable version (5.1.5) and confirm that is still an issue.  The 5.0 branch is no longer maintained.

[Bernd Wiebus (bernd-wiebus)]

Hello Michael.

> Please upgrade to the latest stable version (5.1.5) and confirm that is
> still an issue.  The 5.0 branch is no longer maintained.

I upgraded to 5.1.5 +dfsg1-2, release build and tested the same schematic i put in the "KiCad_ERC-Error_24Nov2019.zip" file.
Result is the same, no error or warning where i would expect one.
Please note, the schematic is just a very simple schematic to prove the situation.

Full text of KiCad-Version below.

With best regards: Bernd Wiebus alias dl1eic

Application: Eeschema
Version: 5.1.5+dfsg1-2, release build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.0 OpenSSL/1.1.1d zlib/1.2.11 libidn2/2.0.5 libpsl/0.20.2 (+libidn2/2.0.5) libssh2/1.8.0 nghttp2/1.36.0 librtmp/2.3
Platform: Linux 4.19.0-6-686-pae i686, 32 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
    Boost: 1.67.0
    OpenCASCADE Technology: 7.3.0
    Curl: 7.66.0
    Compiler: GCC 9.2.1 with C++ ABI 1013

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=ON
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=ON
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=OFF
    KICAD_USE_OCC=ON
    KICAD_SPICE=ON

[Michael Kavanagh (michaelkavanagh)]

Looks like this is fixed in master (see screenshot) but broken in 5.1.

[KiCad Janitor (kicad-janitor)]

KiCad bug tracker has moved to Gitlab. This report is now available here: https://gitlab.com/kicad/code/kicad/-/issues/1828