Removed the extra CPP and LD flags due to Compilation errors

[cirode]

I've been having errors with compilation on my new MBP

ld: warning: directory not found for option '-L/Users/XXX/personal_code/R-build/3.4.0/lib'
Undefined symbols for architecture x86_64:
  "_pcre_assign_jit_stack", referenced from:
      _setup_jit in grep.o
  "_pcre_free_study", referenced from:
      _do_strsplit in grep.o
      _do_grep in grep.o
      _do_gsub in grep.o
      _do_regexpr in grep.o
  "_pcre_jit_stack_alloc", referenced from:
      _setup_jit in grep.o
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status
make[3]: *** [R.bin] Error 1
make[2]: *** [R] Error 2
make[1]: *** [R] Error 1
make: *** [R] Error 1

BUILD FAILED

Inspect or clean up the working tree at /var/folders/fm/wcc7_6t151q6x0tf1xwjxk7h0000gn/T/R-build.20170726211443.17830
Results logged to /var/folders/fm/wcc7_6t151q6x0tf1xwjxk7h0000gn/T/R-build.20170726211443.17830.log

Last 10 log lines:
      _do_gsub in grep.o
      _do_regexpr in grep.o
  "_pcre_jit_stack_alloc", referenced from:
      _setup_jit in grep.o
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status
make[3]: *** [R.bin] Error 1
make[2]: *** [R] Error 2
make[1]: *** [R] Error 1
make: *** [R] Error 1

Info about my system

• OSX 10.12.5
• gcc

  Apple LLVM version 8.1.0 (clang-802.0.42)
  Target: x86_64-apple-darwin16.6.0
  

• gcc from brew

  gcc-7 (Homebrew GCC 7.1.0 --with-jit --with-nls) 7.1.0
  

I found that I was able to download and compile R 3.4.0 using the following procedure ( using LLVM )

wget  https://cran.r-project.org/src/base/R-3/R-3.4.0.tar.gz
tar -zxvf R-3.4.0.tar.gz
cd R-3.4.0
./configure --prefix=/PATH/TO/INSTALL --enable-R-shlib
make
make install

Reading through the code here I could see a couple of differences; the majour two being the gcc being used, and these flags

hardcoding the gcc to use LLVM gcc did not help, but removing these flags did. I am unsure if these flags were needed for a previous version of R. If so, i'll be happy to modify the pull request