Improve build types and refactor PHP_EXTENSION_DIR

For the time being this adds a new way of assembling the
PHP_EXTENSION_DIR variable that is more "correct" way and relevant as
there are different build types. Since this value is not "guessable"
and needs to be retrieved by the config script, pkg-config, or some find
module, this doesn't make any difference from the CMake-based build
system PoV. But will be probably in need of more refactorings later on.

Author: petk

cmake/cmake/BuildTypes.cmake

@@ -20,14 +20,13 @@ block()
     else()
       set(
         allowedBuildTypes
-          Debug           # Debug info, assertions, not optimized.
-          DebugAssertions # Custom PHP debug build type with assertions enabled
-                          # in the RelWithDebInfo mode: optimized, debug info,
-                          # assertions.
+          Debug           # Not optimized, debug info, assertions.
+          DebugAssertions # Custom PHP debug build type based on RelWithDebInfo:
+                          # optimized, debug info, assertions.
           MinSizeRel      # Same as Release but optimized for size rather than
                           # speed.
-          Release         # No debug info, no assertions, optimized.
-          RelWithDebInfo  # Debug info, optimized, no assertions.
+          Release         # Optimized, no debug info, no assertions.
+          RelWithDebInfo  # Optimized, debug info, no assertions.
       )
 
       set_property(
@@ -48,19 +47,22 @@ block()
   endif()
 endblock()
 
-target_compile_definitions(
-  php_configuration
-  INTERFACE
-    $<IF:$<CONFIG:Debug,DebugAssertions>,ZEND_DEBUG=1,ZEND_DEBUG=0>
-)
-
 # Set CMAKE_<LANG>_FLAGS_<CONFIG> variables for the DebugAssertions build type.
-foreach(prefix CMAKE_C_FLAGS CMAKE_CXX_FLAGS CMAKE_ASM_FLAGS)
+# These should ideally be set for all languages needed for the project scope
+# before adding binary targets that need these flags (for example, PHP
+# extensions or SAPIs).
+foreach(lang C CXX ASM)
   string(
     REGEX REPLACE
     "(-DNDEBUG|/DNDEBUG)"
     ""
-    ${prefix}_DEBUGASSERTIONS
-    "${${prefix}_RELWITHDEBINFO}"
+    CMAKE_${lang}_FLAGS_DEBUGASSERTIONS
+    "${CMAKE_${lang}_FLAGS_RELWITHDEBINFO}"
   )
 endforeach()
+
+target_compile_definitions(
+  php_configuration
+  INTERFACE
+    $<IF:$<CONFIG:Debug,DebugAssertions>,ZEND_DEBUG=1,ZEND_DEBUG=0>
+)

cmake/cmake/Configuration.cmake

@@ -182,25 +182,24 @@ set(
 )
 mark_as_advanced(PHP_EXTENSION_DIR)
 
+# Assemble the PHP_EXTENSION_DIR default value.
 block()
   if(NOT PHP_EXTENSION_DIR)
     file(READ ${PHP_SOURCE_DIR}/Zend/zend_modules.h content)
     string(REGEX MATCH "#define ZEND_MODULE_API_NO ([0-9]*)" _ "${content}")
-    set(zend_module_api_no ${CMAKE_MATCH_1})
+    set(zendModuleApiNo ${CMAKE_MATCH_1})
 
-    set(extension_dir "${CMAKE_INSTALL_LIBDIR}/php")
+    set(
+      extensionDir
+      "${CMAKE_INSTALL_LIBDIR}/php/${zendModuleApiNo}$<$<BOOL:$<TARGET_PROPERTY:php_configuration,PHP_THREAD_SAFETY>>:-zts>$<$<BOOL:$<CONFIG>>:-$<CONFIG>>"
+    )
 
-    # This resembles the PHP Autotools --with-layout=GNU:
-    set(extension_dir "${extension_dir}/${zend_module_api_no}")
-    set(extension_dir "${extension_dir}$<$<BOOL:$<TARGET_PROPERTY:php_configuration,PHP_THREAD_SAFETY>>:-zts>")
-    set(extension_dir "${extension_dir}$<$<CONFIG:Debug,DebugAssertions>:-debug>")
-    # This would be the PHP Autotools --with-layout=PHP (default):
-    # set(extension_dir "${extension_dir}/extensions")
-    # set(extension_dir "${extension_dir}/$<IF:$<CONFIG:Debug,DebugAssertions>,debug,no-debug>")
-    # set(extension_dir "${extension_dir}$<IF:$<BOOL:$<TARGET_PROPERTY:php_configuration,PHP_THREAD_SAFETY>>,-zts,-non-zts>")
-    # set(extension_dir "${extension_dir}-${zend_module_api_no}")
+    # This would resemble the PHP Autotools --with-layout=GNU:
+    #set(extensionDir "${CMAKE_INSTALL_LIBDIR}/php/${zendModuleApiNo}$<$<BOOL:$<TARGET_PROPERTY:php_configuration,PHP_THREAD_SAFETY>>:-zts>$<$<CONFIG:Debug,DebugAssertions>:-debug>")
+    # This would ressemble the PHP Autotools --with-layout=PHP (default):
+    #set(extensionDir "${CMAKE_INSTALL_LIBDIR}/php/extensions/$<IF:$<CONFIG:Debug,DebugAssertions>,debug,no-debug>$<IF:$<BOOL:$<TARGET_PROPERTY:php_configuration,PHP_THREAD_SAFETY>>,-zts,-non-zts>-${zendModuleApiNo}")
 
-    set_property(CACHE PHP_EXTENSION_DIR PROPERTY VALUE "${extension_dir}")
+    set_property(CACHE PHP_EXTENSION_DIR PROPERTY VALUE "${extensionDir}")
   endif()
 endblock()