[lmi-commits] [lmi] master df07870: Fix defect introduced 20170105T0007Z: x86_64 configuration failure

[Greg Chicares]

branch: master
commit df07870f7e56a6b7814571e53dd25361ae3cec81
Author: Gregory W. Chicares <address@hidden>
Commit: Gregory W. Chicares <address@hidden>

    Fix defect introduced 20170105T0007Z: x86_64 configuration failure
---
 config.hpp |   50 ++++++++++++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 18 deletions(-)

diff --git a/config.hpp b/config.hpp
index 7f0557b..2af2251 100644
--- a/config.hpp
+++ b/config.hpp
@@ -68,8 +68,35 @@ namespace fs = boost::filesystem;
 #   error Unknown hardware. Consider contributing support.
 #endif // Unknown hardware.
 
-#if defined __GNUC__
+// Test for x87.
+//
+// For gcc, test the __SSE_MATH__ macro. It might seem logical to test
+// the __SSE__ macro instead; however, for x86_64, gcc defines __SSE__
+// even if SSE is explicitly disabled with '-mfpmath=387'.
+//
+// The _M_IX86_FP test is conditional on _MSC_VER. It would be
+// slightly better to use LMI_MSC in the conditional instead, but
+// that doesn't justify moving this test block far away from where
+// LMI_X86 is set. See:
+//   http://lists.nongnu.org/archive/html/lmi/2017-01/msg00009.html
+
+#if defined LMI_X86
+#   if defined __GNUC__
+#       if !defined __SSE_MATH__
+#           define LMI_X87
+#       endif // !defined __SSE_MATH__
+#   elif defined _MSC_VER
+#       if defined _M_IX86_FP && _M_IX86_FP == 0
+#           define LMI_X87
+#       endif // defined _M_IX86_FP && _M_IX86_FP == 0
+#   else   // Unknown compiler.
+#       error Unknown compiler--cannot detect SSE. Consider contributing 
support.
+#   endif  // Unknown compiler.
+#endif // defined LMI_X86
+
 // This selects a correct snprintf() for MinGW-w64.
+
+#if defined __GNUC__
 #   if !defined _ISOC99_SOURCE
 #       define _ISOC99_SOURCE
 #   endif // !defined _ISOC99_SOURCE
@@ -139,7 +166,10 @@ namespace fs = boost::filesystem;
 
 // Give this toolchain its own lmi-specific macro. Rationale:
 //   http://boost.cvs.sf.net/boost/boost/boost/config.hpp?annotate=1.1
-//   Many other "compilers define _MSC_VER. Thus BOOST_MSVC."
+//   Many other "compilers define _MSC_VER. Thus BOOST_MSVC. [...]
+//   Must remain the last #elif since some other vendors (Metrowerks,
+//   for example) also #define _MSC_VER"
+
 #if defined _MSC_VER && !defined LMI_GCC_VERSION && !defined 
LMI_COMO_WITH_MINGW
 #    define LMI_MSC
 #endif // defined _MSC_VER && !defined LMI_GCC_VERSION && !defined 
LMI_COMO_WITH_MINGW
@@ -148,22 +178,6 @@ namespace fs = boost::filesystem;
 #   define LMI_MSVCRT
 #endif // Compilers that use the msvc C runtime, without corrections such as 
libmingwex.
 
-// Test for x87.
-//
-// For gcc, test the __SSE_MATH__ macro. It might seem logical to test
-// the __SSE__ macro instead; however, for x86_64, gcc defines __SSE__
-// even if SSE is explicitly disabled with '-mfpmath=387'.
-
-#if defined LMI_X86
-#   if defined __GNUC__ && !defined __SSE_MATH__
-#       define LMI_X87
-#   elif defined LMI_MSC && defined _M_IX86_FP && _M_IX86_FP == 0
-#       define LMI_X87
-#   else   // Unknown compiler.
-#       error Unknown compiler--cannot detect SSE. Consider contributing 
support.
-#   endif  // Unknown compiler.
-#endif // defined LMI_X86
-
 #if defined HAVE_CONFIG_H // Using autoconf.
 #   include "config.h"
 #else // Not using autoconf.