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git-svn-id: https://svn.r-project.org/R/trunk@87951 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: ripley

m4/R.m4

@@ -4579,6 +4579,7 @@ LIBS="${r_save_LIBS}"
 if test "x${r_cv_icu}" = xyes; then
   AC_DEFINE(USE_ICU, 1, [Define to use ICU for collation.])
   LIBS="${LIBS} -licuuc -licui18n"
+dnl why does this append when everything else prepends?  Including on macOS
 else
   use_ICU=no
 fi

src/include/R_ext/Boolean.h

@@ -26,6 +26,8 @@
 #ifndef R_EXT_BOOLEAN_H_
 #define R_EXT_BOOLEAN_H_
 
+// NB: there is a version of this in Rmath.h0[.in]
+
 #undef FALSE
 #undef TRUE
 

src/nmath/standalone/Makefile.in

@@ -89,6 +89,9 @@ inc: Makefile
 
 # check: clean  -- takes ~ 5 sec --> just  'rm test':
 #      : all  -- not as dependency, but directly, possibly parallelized:
+### NB: we only test the static library, unlike Windows.
+### This is becuse of the platform-specific and ever-changing ways
+### of finding the just-built DSO/dylib at run time.
 check:
 	@rm -f check.log test
 	@if test -n "${TEST_MC_CORES}"; then \