Redfine macros upon installation.

myapp.spec

# See https://docs.fedoraproject.org/en-US/packaging-guidelines/#_compiler_macros
%global toolchain clang

Name: myapp
Version: 1.0.0
Release: 1%{?dist}
Summary: A simple "Hello, World!" application.

License: Apache-2.0
URL: https://github.com/kwk/hello-world
Source0: myapp-%{version}.tar.bz2

BuildRequires:	clang
BuildRequires:	cmake
BuildRequires:	git

%description
A simple "Hello, World!" application.

%prep
%autosetup -S git

%build
%cmake -DCMAKE_BUILD_TYPE=Release
%cmake_build

%install
%cmake_install
mkdir -p %{buildroot}/%{_rpmmacrodir}
touch %{buildroot}/%{_rpmmacrodir}/macros.my-package

%check
test "`%{buildroot}/%{_bindir}/myapp`" = "Hello, World!"

%triggerin -- redhat-rpm-config
echo "%%__os_install_post \\" > %{_rpmmacrodir}/macros.my-package
rpm --eval "%%{macrobody:__os_install_post}"  \
    | sed '/^%%{nil}/!s,$, \\,' \
    | sed 's/%%{nil}/%%{__llvm_pgo_instrumented_os_install_post} \\\n%%{nil}/' >> %{_rpmmacrodir}/macros.my-package

%files
%license LICENSE
%{_rpmmacrodir}/macros.my-package
%{_bindir}/myapp

%changelog
* Wed Mar 1 2023 john doe [email protected]> - 1.0.0-1
- Building step1