HPCC-31366 Replace Boost regex with PCRE2 regex

Use PCRE2 specifically for STRING regex work.  UTF-8 and Unicode regex remains untouched for now.

.gitignore

@@ -18,4 +18,4 @@ eclcc.log
 ./dockerfiles/platform-build-incremental/hpcc.gitpatch
 dockerfiles/platform-build-incremental/hpcc.gitpatch
 .env
-/vcpkg.json
+/vcpkg.json

cmake_modules/commonSetup.cmake

@@ -839,11 +839,6 @@ IF ("${COMMONSETUP_DONE}" STREQUAL "")
         endif()
       endif(USE_URIPARSER)
 
-      find_package(Boost COMPONENTS regex)
-	  if (NOT Boost_REGEX_FOUND)
-		message(FATAL_ERROR "BOOST_REGEX required but package not found")
-	  endif()
-
       if(USE_PARQUET)
         message(STATUS "Parquet enabled")
         add_definitions(-D_USE_PARQUET)

cmake_modules/options.cmake

@@ -17,7 +17,6 @@ option(SIGN_MODULES "Enable signing of ecl standard library modules" OFF)
 option(USE_CPPUNIT "Enable unit tests (requires cppunit)" OFF)
 option(USE_OPENLDAP "Enable OpenLDAP support (requires OpenLDAP)" ON)
 option(USE_ICU "Enable unicode support (requires ICU)" ON)
-option(Boost_USE_STATIC_LIBS "Use boost_regex static library for RPM BUILD" OFF)
 option(USE_OPENSSL "Configure use of OpenSSL" ON)
 option(USE_OPENSSLV3 "Configure use of OpenSSL Version 3 or newer" ON)
 option(USE_ZLIB "Configure use of zlib" ON)

rtl/eclrtl/CMakeLists.txt

@@ -76,7 +76,6 @@ include_directories (
          ./../../system/jlib 
          ./../../roxie/roxiemem
          ./../../testing/unittests
-         ${Boost_INCLUDE_DIRS}
     )
 
 ADD_DEFINITIONS( -D_USRDLL -DECLRTL_EXPORTS )
@@ -87,7 +86,8 @@ endif ()
 
 HPCC_ADD_LIBRARY( eclrtl SHARED ${SRCS} )
 
-target_link_libraries( eclrtl Boost::boost Boost::regex )
+find_package(pcre2 CONFIG REQUIRED)
+target_link_libraries( eclrtl PCRE2::8BIT PCRE2::16BIT )
 
 target_link_libraries ( eclrtl 
       jlib