ENH: Generalize the check for sizeof void* to detect more ABI information.

Modules/CMakeCCompiler.cmake.in

@@ -23,6 +23,14 @@ SET(CMAKE_C_SOURCE_FILE_EXTENSIONS c)
 SET(CMAKE_C_IGNORE_EXTENSIONS h;H;o;O;obj;OBJ;def;DEF;rc;RC)
 SET(CMAKE_C_LINKER_PREFERENCE 10)
 
-# save the size of void* in case where cache is removed
-# and the this file is still around
-SET(CMAKE_SIZEOF_VOID_P @CMAKE_SIZEOF_VOID_P@)
+# Save compiler ABI information.
+SET(CMAKE_C_SIZEOF_DATA_PTR "@CMAKE_C_SIZEOF_DATA_PTR@")
+SET(CMAKE_C_COMPILER_ABI "@CMAKE_C_COMPILER_ABI@")
+
+IF(CMAKE_C_SIZEOF_DATA_PTR)
+  SET(CMAKE_SIZEOF_VOID_P "${CMAKE_C_SIZEOF_DATA_PTR}")
+ENDIF(CMAKE_C_SIZEOF_DATA_PTR)
+
+IF(CMAKE_C_COMPILER_ABI)
+  SET(CMAKE_INTERNAL_PLATFORM_ABI "${CMAKE_C_COMPILER_ABI}")
+ENDIF(CMAKE_C_COMPILER_ABI)

Modules/CMakeCCompilerABI.c

+#ifdef __cplusplus
+# error "A C++ compiler has been selected for C."
+#endif
+
+#ifdef __CLASSIC_C__
+# define const
+#endif
+
+/*--------------------------------------------------------------------------*/
+
+#include "CMakeCompilerABI.h"
+
+/*--------------------------------------------------------------------------*/
+
+/* Make sure the information strings are referenced.  */
+#define REQUIRE(x) (&x[0] != &require)
+
+int main()
+{
+  const char require = 0;
+  return
+    (
+      REQUIRE(info_sizeof_dptr)
+#if defined(ABI_ID)
+      && REQUIRE(info_abi)
+#endif
+      );
+}

Modules/CMakeCXXCompiler.cmake.in

@@ -23,6 +23,14 @@ SET(CMAKE_CXX_IGNORE_EXTENSIONS inl;h;H;o;O;obj;OBJ;def;DEF;rc;RC)
 SET(CMAKE_CXX_SOURCE_FILE_EXTENSIONS C;M;c++;cc;cpp;cxx;m;mm)
 SET(CMAKE_CXX_LINKER_PREFERENCE 30)
 
-# save the size of void* in case where cache is removed
-# and the this file is still around
-SET(CMAKE_SIZEOF_VOID_P @CMAKE_SIZEOF_VOID_P@)
+# Save compiler ABI information.
+SET(CMAKE_CXX_SIZEOF_DATA_PTR "@CMAKE_CXX_SIZEOF_DATA_PTR@")
+SET(CMAKE_CXX_COMPILER_ABI "@CMAKE_CXX_COMPILER_ABI@")
+
+IF(CMAKE_CXX_SIZEOF_DATA_PTR)
+  SET(CMAKE_SIZEOF_VOID_P "${CMAKE_CXX_SIZEOF_DATA_PTR}")
+ENDIF(CMAKE_CXX_SIZEOF_DATA_PTR)
+
+IF(CMAKE_CXX_COMPILER_ABI)
+  SET(CMAKE_INTERNAL_PLATFORM_ABI "${CMAKE_CXX_COMPILER_ABI}")
+ENDIF(CMAKE_CXX_COMPILER_ABI)

Modules/CMakeCXXCompilerABI.cpp

+#ifndef __cplusplus
+# error "A C compiler has been selected for C++."
+#endif
+
+/*--------------------------------------------------------------------------*/
+
+#include "CMakeCompilerABI.h"
+
+/*--------------------------------------------------------------------------*/
+
+/* Make sure the information strings are referenced.  */
+#define REQUIRE(x) (&x[0] != &require)
+
+int main()
+{
+  const char require = 0;
+  return
+    (
+      REQUIRE(info_sizeof_dptr)
+#if defined(ABI_ID)
+      && REQUIRE(info_abi)
+#endif
+      );
+}

Modules/CMakeCompilerABI.h

+/*--------------------------------------------------------------------------*/
+
+/* Size of a pointer-to-data in bytes.  */
+#define SIZEOF_DPTR (sizeof(void*))
+const char info_sizeof_dptr[] =  {
+  'I', 'N', 'F', 'O', ':', 's', 'i', 'z', 'e', 'o', 'f', '_', 'd', 'p', 't', 'r', '[',
+  ('0' + ((SIZEOF_DPTR / 10)%10)),
+  ('0' +  (SIZEOF_DPTR    % 10)),
+  ']','\0'};
+
+/*--------------------------------------------------------------------------*/
+
+/* Application Binary Interface.  */
+#if defined(__sgi) && defined(_ABIO32)
+# define ABI_ID "ELF O32"
+#elif defined(__sgi) && defined(_ABIN32)
+# define ABI_ID "ELF N32"
+#elif defined(__sgi) && defined(_ABI64)
+# define ABI_ID "ELF 64"
+#elif defined(__ELF__)
+# define ABI_ID "ELF"
+#endif
+
+#if defined(ABI_ID)
+static char const info_abi[] = "INFO:abi[" ABI_ID "]";
+#endif

Modules/CMakeDetermineCompilerABI.cmake

+
+# Function to compile a source file to identify the compiler ABI.
+# This is used internally by CMake and should not be included by user
+# code.
+
+FUNCTION(CMAKE_DETERMINE_COMPILER_ABI lang src)
+  IF(NOT DEFINED CMAKE_DETERMINE_${lang}_ABI_COMPILED)
+    MESSAGE(STATUS "Detecting ${lang} compiler info")
+
+    # Compile the ABI identification source.
+    SET(BIN "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeDetermineCompilerABI_${lang}.bin")
+    TRY_COMPILE(CMAKE_DETERMINE_${lang}_ABI_COMPILED
+      ${CMAKE_BINARY_DIR} ${src}
+      OUTPUT_VARIABLE OUTPUT
+      COPY_FILE "${BIN}"
+      )
+
+    # Load the resulting information strings.
+    IF(CMAKE_DETERMINE_${lang}_ABI_COMPILED)
+      MESSAGE(STATUS "Detecting ${lang} compiler info - done")
+      FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
+        "Detecting ${lang} compiler info compiled with the following output:\n${OUTPUT}\n\n")
+      FILE(STRINGS "${BIN}" ABI_STRINGS LIMIT_COUNT 2 REGEX "INFO:[^[]*\\[")
+      FOREACH(info ${ABI_STRINGS})
+        IF("${info}" MATCHES ".*INFO:sizeof_dptr\\[0*([^]]*)\\].*")
+          STRING(REGEX REPLACE ".*INFO:sizeof_dptr\\[0*([^]]*)\\].*" "\\1" ABI_SIZEOF_DPTR "${info}")
+        ENDIF("${info}" MATCHES ".*INFO:sizeof_dptr\\[0*([^]]*)\\].*")
+        IF("${info}" MATCHES ".*INFO:abi\\[([^]]*)\\].*")
+          STRING(REGEX REPLACE ".*INFO:abi\\[([^]]*)\\].*" "\\1" ABI_NAME "${info}")
+        ENDIF("${info}" MATCHES ".*INFO:abi\\[([^]]*)\\].*")
+      ENDFOREACH(info)
+
+      IF(ABI_SIZEOF_DPTR)
+        SET(CMAKE_${lang}_SIZEOF_DATA_PTR "${ABI_SIZEOF_DPTR}" PARENT_SCOPE)
+        SET(CMAKE_SIZEOF_VOID_P "${ABI_SIZEOF_DPTR}" PARENT_SCOPE)
+      ENDIF(ABI_SIZEOF_DPTR)
+
+      IF(ABI_NAME)
+        SET(CMAKE_${lang}_COMPILER_ABI "${ABI_NAME}" PARENT_SCOPE)
+        SET(CMAKE_INTERNAL_PLATFORM_ABI "${ABI_NAME}" PARENT_SCOPE)
+      ENDIF(ABI_NAME)
+
+    ELSE(CMAKE_DETERMINE_${lang}_ABI_COMPILED)
+      MESSAGE(STATUS "Detecting ${lang} compiler info - failed")
+      FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
+        "Detecting ${lang} compiler info failed to compile with the following output:\n${OUTPUT}\n\n")
+    ENDIF(CMAKE_DETERMINE_${lang}_ABI_COMPILED)
+  ENDIF(NOT DEFINED CMAKE_DETERMINE_${lang}_ABI_COMPILED)
+ENDFUNCTION(CMAKE_DETERMINE_COMPILER_ABI)

Modules/CMakeTestCCompiler.cmake

@@ -40,14 +40,15 @@ ELSE(NOT CMAKE_C_COMPILER_WORKS)
       "Determining if the C compiler works passed with "
       "the following output:\n${OUTPUT}\n\n") 
   ENDIF(C_TEST_WAS_RUN)
-  INCLUDE (${CMAKE_ROOT}/Modules/CheckTypeSize.cmake)
-  # Check the size of void*.  This used to be "void *" but icc expands the *.
-  CHECK_TYPE_SIZE("void*"  CMAKE_SIZEOF_VOID_P)
   SET(CMAKE_C_COMPILER_WORKS 1 CACHE INTERNAL "")
-  # re-configure this file CMakeCCompiler.cmake so that it gets
-  # the value for CMAKE_SIZEOF_VOID_P
-  # configure variables set in this file for fast reload later on
-  CONFIGURE_FILE(${CMAKE_ROOT}/Modules/CMakeCCompiler.cmake.in 
-    ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCCompiler.cmake IMMEDIATE)
+
+  # Try to identify the ABI and configure it into CMakeCCompiler.cmake
+  INCLUDE(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerABI.cmake)
+  CMAKE_DETERMINE_COMPILER_ABI(C ${CMAKE_ROOT}/Modules/CMakeCCompilerABI.c)
+  CONFIGURE_FILE(
+    ${CMAKE_ROOT}/Modules/CMakeCCompiler.cmake.in
+    ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCCompiler.cmake
+    @ONLY
+    )
 ENDIF(NOT CMAKE_C_COMPILER_WORKS)
 

Modules/CMakeTestCXXCompiler.cmake

@@ -34,4 +34,13 @@ ELSE(NOT CMAKE_CXX_COMPILER_WORKS)
       "the following output:\n${OUTPUT}\n\n")
   ENDIF(CXX_TEST_WAS_RUN)
   SET(CMAKE_CXX_COMPILER_WORKS 1 CACHE INTERNAL "")
+
+  # Try to identify the ABI and configure it into CMakeCXXCompiler.cmake
+  INCLUDE(${CMAKE_ROOT}/Modules/CMakeDetermineCompilerABI.cmake)
+  CMAKE_DETERMINE_COMPILER_ABI(CXX ${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp)
+  CONFIGURE_FILE(
+    ${CMAKE_ROOT}/Modules/CMakeCXXCompiler.cmake.in
+    ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCXXCompiler.cmake
+    @ONLY
+    )
 ENDIF(NOT CMAKE_CXX_COMPILER_WORKS)

Source/cmDocumentVariables.cxx

@@ -839,6 +839,27 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      false,
      "Variables for Languages");
 
+  cm->DefineProperty
+    ("CMAKE_<LANG>_COMPILER_ABI", cmProperty::VARIABLE,
+     "An internal variable subject to change.",
+     "This is used in determining the compiler ABI and is subject to change.",
+     false,
+     "Variables for Languages");
+
+  cm->DefineProperty
+    ("CMAKE_INTERNAL_PLATFORM_ABI", cmProperty::VARIABLE,
+     "An internal variable subject to change.",
+     "This is used in determining the compiler ABI and is subject to change.",
+     false,
+     "Variables for Languages");
+
+  cm->DefineProperty
+    ("CMAKE_<LANG>_SIZEOF_DATA_PTR", cmProperty::VARIABLE,
+     "An internal variable subject to change.",
+     "This is used in determining the architecture and is subject to change.",
+     false,
+     "Variables for Languages");
+
   cm->DefineProperty
     ("CMAKE_COMPILER_IS_GNU<LANG>", cmProperty::VARIABLE,
      "True if the compiler is GNU.",