Fixes Issue 19194 - version for -mscrtlib specification

Add __CXXLIB__ predefined enum.
dlang · Sep 19, 2018 · 0563a79 · 0563a79
1 parent a705f11
commit 0563a79
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diff --git a/changelog/mscrt_ver.dd b/changelog/mscrt_ver.dd
@@ -0,0 +1,8 @@
+Add `__CXXLIB__` built-in enum.
+
+Query the C++ library version for the compilation target at compile time, eg:
+---
+static if (__CXXLIB__ == "libcmtd") { ... }
+---
+
+Currently only supported for MS-COFF output, and will be an empty string for other targets.
diff --git a/src/dmd/doc.d b/src/dmd/doc.d
@@ -2126,6 +2126,7 @@ private bool isReservedName(const(char)[] str)
         "__VENDOR__",
         "__VERSION__",
         "__EOF__",
+        "__CXXLIB__",
         "__LOCAL_SIZE",
         "___tls_get_addr",
         "__entrypoint",

diff --git a/src/dmd/id.d b/src/dmd/id.d
@@ -159,6 +159,7 @@ immutable Msgtable[] msgtable =
     { "VENDOR", "__VENDOR__" },
     { "VERSIONX", "__VERSION__" },
     { "EOFX", "__EOF__" },
+    { "CXXLIB", "__CXXLIB__" },
 
     { "nan" },
     { "infinity" },

diff --git a/src/dmd/lexer.d b/src/dmd/lexer.d
@@ -530,6 +530,24 @@ class Lexer : ErrorHandler
                             t.ustring = global.compiler.vendor;
                             goto Lstr;
                         }
+                        else if (id == Id.CXXLIB)
+                        {
+                            // TODO: other targets might also like to populate this with knowledge for library authors
+                            //       additional plumbing required...
+                            if (!global.params.mscrtlib)
+                            {
+                                t.ustring = "";
+                            }
+                            else
+                            {
+                                size_t len = strlen(global.params.mscrtlib) + 1;
+                                char* lower = cast(char*)mem.xmalloc(len);
+                                foreach (i; 0 .. len)
+                                    lower[i] = cast(char)tolower(global.params.mscrtlib[i]);
+                                t.ustring = lower;
+                            }
+                            goto Lstr;
+                        }
                         else if (id == Id.TIMESTAMP)
                         {
                             t.ustring = timestamp.ptr;

diff --git a/test/compilable/cpp.d b/test/compilable/cpp.d
@@ -0,0 +1,11 @@
+
+// Test C++ features.
+
+version(CRuntime_Microsoft)
+{
+    static assert(__CXXLIB__ == "libcmt");
+}
+else
+{
+    static assert(__CXXLIB__.length == 0);
+}