Hear you go:
$PETSC_DIR/$PETSC_ARCH/bin/mpicc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/usr/include/c++/4.2.1
Apple LLVM version 10.0.1 (clang-1001.0.46.4)
Target: x86_64-apple-darwin18.5.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
$PETSC_DIR/$PETSC_ARCH/bin/mpif90 -v
Using built-in specs.
COLLECT_GCC=/usr/local/bin/gfortran
COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/8.3.0/libexec/gcc/x86_64-apple-darwin18.2.0/8.3.0/lto-wrapper
Target: x86_64-apple-darwin18.2.0
Configured with: ../configure --build=x86_64-apple-darwin18.2.0 --prefix=/usr/local/Cellar/gcc/8.3.0 --libdir=/usr/local/Cellar/gcc/8.3.0/lib/gcc/8 --disable-nls --enable-checking=release --enable-languages=c,c++,objc,obj-c++,fortran --program-suffix=-8 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-system-zlib --with-pkgversion='Homebrew GCC 8.3.0' --with-bugurl=https://github.com/Homebrew/homebrew-core/issues --disable-multilib --with-native-system-header-dir=/usr/include --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk
Thread model: posix
gcc version 8.3.0 (Homebrew GCC 8.3.0)
gcc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/usr/include/c++/4.2.1
Apple LLVM version 10.0.1 (clang-1001.0.46.4)
Target: x86_64-apple-darwin18.5.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
gfortran -v
Using built-in specs.
COLLECT_GCC=gfortran
COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/8.3.0/libexec/gcc/x86_64-apple-darwin18.2.0/8.3.0/lto-wrapper
Target: x86_64-apple-darwin18.2.0
Configured with: ../configure --build=x86_64-apple-darwin18.2.0 --prefix=/usr/local/Cellar/gcc/8.3.0 --libdir=/usr/local/Cellar/gcc/8.3.0/lib/gcc/8 --disable-nls --enable-checking=release --enable-languages=c,c++,objc,obj-c++,fortran --program-suffix=-8 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-system-zlib --with-pkgversion='Homebrew GCC 8.3.0' --with-bugurl=https://github.com/Homebrew/homebrew-core/issues --disable-multilib --with-native-system-header-dir=/usr/include --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk
Thread model: posix
gcc version 8.3.0 (Homebrew GCC 8.3.0)
From my petsc configure.log
Configure Options: --configModules=PETSc.Configure --optionsModule=config.compilerOptions --download-parmetis --download-superlu_dist --download-openmpi --download-ml --download-hypre --download-metis --download-mumps --download-scalapack --download-blacs --with-debugging=0