try to help detection of intel compiler

Author: kevinushey

tools/config/configure.R

@@ -24,7 +24,7 @@ if (file.exists(makevars)) {
 
 # Figure out the appropriate CXX prefix for the current
 # version of R + configuration.
-cxx <- NULL
+cxx <- "/usr/bin/c++"
 candidates <- c("CXX11", "CXX1X", "CXX")
 for (candidate in candidates) {
    value <- r_cmd_config(candidate)
@@ -34,6 +34,11 @@ for (candidate in candidates) {
    }
 }
 
+# Check for the intel compiler
+if (any(grepl("icpc", cxx, fixed = TRUE))) {
+   define(COMPILER = "icpc")
+}
+
 # work around issue with '-Werror=format-security' being specified without
 # a prior '-Wformat', which makes gcc angry
 cxxflags <- read_r_config(sprintf("%sFLAGS", cxx), envir = NULL)[[1]]