Use toolchain macro instead of hard-coding gcc

miniz.spec

@@ -16,7 +16,15 @@ Patch0:     miniz-2.1.0-Examples-to-include-system-miniz.h.patch
 BuildRequires:  coreutils
 # diffutils for cmp
 BuildRequires:  diffutils
+%if "%{toolchain}" == "gcc"
 BuildRequires:  gcc
+%else
+%if "%{toolchain}" == "clang"
+BuildRequires:  clang
+%else
+%{error:Unknown toolchain.}
+%endif
+%endif
 BuildRequires:  sed
 BuildRequires:  unzip
 
@@ -51,10 +59,12 @@ mv ChangeLog.md.new ChangeLog.md
 %global soname lib%{name}.so.0.2
 
 %build
+# Export CC environment variable
+%{set_build_flags}
 # Inject downstream SONAME, bug #1152653
-%{__cc} %{optflags} -fPIC -DPIC -D_LARGEFILE64_SOURCE=1 -D_FILE_OFFSET_BITS=64 \
+"$CC" %{optflags} -fPIC -DPIC -D_LARGEFILE64_SOURCE=1 -D_FILE_OFFSET_BITS=64 \
     %{name}.c -c -o %{name}.o
-%{__cc} %{?__global_ldflags} -fPIC -shared -Wl,-soname,%{soname} \
+"$CC" %{?__global_ldflags} -fPIC -shared -Wl,-soname,%{soname} \
     %{name}.o -o %{soname}
 ln -s %{soname} lib%{name}.so
 # Build examples against the library
@@ -118,7 +128,7 @@ install -m 0644 %{name}.h '%{buildroot}/%{_includedir}'
 
 %changelog
 * Mon Jan 25 2021 Tom Stellard <tstellar@redhat.com> - 2.1.0-6
-- Use __cc macro instead of hard-coding gcc
+- Use toolchain macro instead of hard-coding gcc
 
 * Tue Jul 28 2020 Fedora Release Engineering <releng@fedoraproject.org> - 2.1.0-5
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_33_Mass_Rebuild