Improve a couple of CMake checks

Author: NWilson

CMakeLists.txt

@@ -450,32 +450,45 @@ if(BZIP2_FOUND)
   option(PCRE2_SUPPORT_LIBBZ2 "Enable support for linking pcre2grep with libbz2." ON)
 endif()
 if(PCRE2_SUPPORT_LIBBZ2)
-  include_directories(${BZIP2_INCLUDE_DIR})
+  if(BZIP2_FOUND)
+    include_directories(${BZIP2_INCLUDE_DIR})
+  else()
+    message(
+      FATAL_ERROR
+      " libbz2 not found. Set BZIP2_INCLUDE_DIR to a compatible header\n"
+      " or set BZip2_ROOT to a full bzip2 installed tree, as needed."
+    )
+  endif()
 endif()
 
 # zlib
 if(ZLIB_FOUND)
   option(PCRE2_SUPPORT_LIBZ "Enable support for linking pcre2grep with libz." ON)
 endif()
 if(PCRE2_SUPPORT_LIBZ)
-  include_directories(${ZLIB_INCLUDE_DIR})
+  if(ZLIB_FOUND)
+    include_directories(${ZLIB_INCLUDE_DIR})
+  else()
+    message(
+      FATAL_ERROR
+      " zlib not found. Set ZLIB_INCLUDE_DIR to a compatible header\n"
+      " or set ZLIB_ROOT to a full zlib installed tree, as needed."
+    )
+  endif()
 endif()
 
 # editline lib
 if(EDITLINE_FOUND)
   option(PCRE2_SUPPORT_LIBEDIT "Enable support for linking pcre2test with libedit." OFF)
 endif()
-if(EDITLINE_FOUND)
-  if(PCRE2_SUPPORT_LIBEDIT)
+if(PCRE2_SUPPORT_LIBEDIT)
+  if(EDITLINE_FOUND)
     include_directories(${EDITLINE_INCLUDE_DIR})
-  endif()
-else()
-  if(PCRE2_SUPPORT_LIBEDIT)
+  else()
     message(
       FATAL_ERROR
-      " libedit not found, set EDITLINE_INCLUDE_DIR to a compatible header\n"
-      " or set Editline_ROOT to a full libedit installed tree, as needed\n"
-      " Might need to enable policy CMP0074 in CMakeLists.txt"
+      " libedit not found. Set EDITLINE_INCLUDE_DIR to a compatible header\n"
+      " or set Editline_ROOT to a full libedit installed tree, as needed."
     )
   endif()
 endif()
@@ -485,7 +498,15 @@ if(READLINE_FOUND)
   option(PCRE2_SUPPORT_LIBREADLINE "Enable support for linking pcre2test with libreadline." ON)
 endif()
 if(PCRE2_SUPPORT_LIBREADLINE)
-  include_directories(${READLINE_INCLUDE_DIR})
+  if(READLINE_FOUND)
+    include_directories(${READLINE_INCLUDE_DIR})
+  else()
+    message(
+      FATAL_ERROR
+      " libreadline not found. Set READLINE_INCLUDE_DIR to a compatible header\n"
+      " or set Readline_ROOT to a full libreadline installed tree, as needed."
+    )
+  endif()
 endif()
 
 # Prepare build configuration
@@ -1493,7 +1514,12 @@ if(PCRE2_SHOW_REPORT)
     endforeach()
   else()
     string(TOUPPER "${CMAKE_BUILD_TYPE}" buildtype)
-    message(STATUS "  C compiler flags .................. : ${CMAKE_C_FLAGS}${CFSP}${CMAKE_C_FLAGS_${buildtype}}")
+    if(buildtype STREQUAL "")
+      set(CFBLD "")
+    else()
+      set(CFBLD "${CMAKE_C_FLAGS_${buildtype}}")
+    endif()
+    message(STATUS "  C compiler flags .................. : ${CMAKE_C_FLAGS}${CFSP}${CFBLD}")
   endif()
 
   message(STATUS "")

cmake/PCRE2UseSystemExtensions.cmake

@@ -28,43 +28,53 @@ function(pcre2_use_system_extensions)
   cmake_push_check_state(RESET)
   set(
     _pcre2_test_src
-    "
-#include <sys/time.h>
-#include <sys/resource.h>
+    [=[
+    #include <sys/time.h>
+    #include <sys/resource.h>
 
-int main(void) {
-    struct rlimit rlim;
-    getrlimit(RLIMIT_STACK, &rlim);
-    return 0;
-}
-"
+    int main(void) {
+        struct rlimit rlim;
+        getrlimit(RLIMIT_STACK, &rlim);
+        return 0;
+    }
+    ]=]
   )
   set(CMAKE_REQUIRED_QUIET TRUE)
   check_c_source_compiles("${_pcre2_test_src}" _HAVE_GETRLIMIT_NAKED)
 
   if(NOT _HAVE_GETRLIMIT_NAKED)
     # Try again with _ALL_SOURCE
+    if(NOT _HAVE_GETRLIMIT_ALLSOURCE)
+      set(_allsource_first_run TRUE)
+    endif()
     set(CMAKE_REQUIRED_DEFINITIONS "-D_ALL_SOURCE")
     check_c_source_compiles("${_pcre2_test_src}" _HAVE_GETRLIMIT_ALLSOURCE)
     unset(CMAKE_REQUIRED_DEFINITIONS)
 
     if(_HAVE_GETRLIMIT_ALLSOURCE)
-      message(STATUS "Detected platform feature gate _ALL_SOURCE")
       add_compile_definitions(_ALL_SOURCE)
+      if(_allsource_first_run)
+        message(STATUS "Detected platform feature gate _ALL_SOURCE")
+      endif()
     endif()
   endif()
 
   check_symbol_exists(mkostemp stdlib.h _HAVE_MKOSTEMP_NAKED)
 
   if(NOT _HAVE_MKOSTEMP_NAKED)
     # Try again with _GNU_SOURCE
+    if(NOT _HAVE_MKOSTEMP_GNUSOURCE)
+      set(_gnusource_first_run TRUE)
+    endif()
     set(CMAKE_REQUIRED_DEFINITIONS "-D_GNU_SOURCE")
     check_symbol_exists(mkostemp stdlib.h _HAVE_MKOSTEMP_GNUSOURCE)
     unset(CMAKE_REQUIRED_DEFINITIONS)
 
     if(_HAVE_MKOSTEMP_GNUSOURCE)
-      message(STATUS "Detected platform feature gate _GNU_SOURCE")
       add_compile_definitions(_GNU_SOURCE)
+      if(_gnusource_first_run)
+        message(STATUS "Detected platform feature gate _GNU_SOURCE")
+      endif()
     endif()
   endif()