Compiler error in gvm-libs/base/networking.c due to extra parentheses

[rpfeiffer]

When compiling the gvm-libs branch (master and 20.8.x) the compiler reports the error "equality comparison with extraneous parentheses". Due to the -Werror flag set the warning is turned into an error and the compilation does not finish

Expected behavior

Expectation is to finish the build process.

Actual behavior

Compilation stops with:

/tmp/gvm-libs/base/networking.c:654:27: error: equality comparison with extraneous parentheses [-Werror,-Wparentheses-equality]
if ((element[0] == 'T'))
~~~~~~~~~~~^~~~~~
/tmp/gvm-libs/base/networking.c:654:27: note: remove extraneous parentheses around the comparison to silence this warning
if ((element[0] == 'T'))
~ ^ ~
/tmp/gvm-libs/base/networking.c:654:27: note: use '=' to turn this equality comparison into an assignment
if ((element[0] == 'T'))
^~
=
/tmp/gvm-libs/base/networking.c:665:32: error: equality comparison with extraneous parentheses [-Werror,-Wparentheses-equality]
else if ((element[0] == 'U'))
~~~~~~~~~~~^~~~~~
/tmp/gvm-libs/base/networking.c:665:32: note: remove extraneous parentheses around the comparison to silence this warning
else if ((element[0] == 'U'))
~ ^ ~
/tmp/gvm-libs/base/networking.c:665:32: note: use '=' to turn this equality comparison into an assignment
else if ((element[0] == 'U'))
^~
=
2 errors generated.

Steps to reproduce

1. git clone https://github.com/greenbone/gvm-libs.git
2. cd gvm-libs/
3. export CC=clang-12
4. export CXX=clang++-12
5. mkdir build && cd build && cmake -DCMAKE_INSTALL_PREFIX=/opt/gvm .. && make && make doc

GVM versions

Since gvm-libs is the first package to install, there are no installed versions.

Environment

Operating system:

• Debian 10 with backports and clang repostory enabled
• Linux host 5.10.11 Adapt CPack Resources to file name change #1 SMP Wed Jan 27 18:35:21 CET 2021 x86_64 GNU/Linux

Fix

Remove the extraneous parentheses in the following files:

• gvm-libs/base/networking.c:654:27
• gvm-libs/base/networking.c:665:32

After removing the extraneous parentheses the code compiles successfully.

[y0urself]

Do you want to provide a PR yourself?

[rpfeiffer]

No, I just want to create a deployment playbook to install OpenVAS by using Ansible. Compiler errors tend to break automatisation. I used no special compile options to check the code for errors, i.e. I did not activate "-Werror,-Wparentheses-equality" on purpose. I just happen to use Clang 12 at the moment.

[y0urself]

This message also appears for clang-7.