[PATCH] Properly handle glibc (that is, GNU environment) cases.

[Thomas Schwinge]

---
 lib/Support/DynamicLibrary.cpp   |    4 +--
 lib/Target/TargetLibraryInfo.cpp |   69 +++++++++++++++++++++++++++++---------
 2 files changed, 56 insertions(+), 17 deletions(-)

diff --git lib/Support/DynamicLibrary.cpp lib/Support/DynamicLibrary.cpp
index f14cb45..b398809 100644
--- lib/Support/DynamicLibrary.cpp
+++ lib/Support/DynamicLibrary.cpp
@@ -157,10 +157,10 @@ void* DynamicLibrary::SearchForAddressOfSymbol(const char *symbolName) {
 #define EXPLICIT_SYMBOL(SYM) \
    if (!strcmp(symbolName, #SYM)) return &SYM
 
-// On linux we have a weird situation. The stderr/out/in symbols are both
+// With glibc, the stderr/stdout/stdin symbols are both
 // macros and global variables because of standards requirements. So, we
 // boldly use the EXPLICIT_SYMBOL macro without checking for a #define first.
-#if defined(__linux__) and !defined(__ANDROID__)
+#ifdef __GLIBC__
   {
     EXPLICIT_SYMBOL(stderr);
     EXPLICIT_SYMBOL(stdout);
diff --git lib/Target/TargetLibraryInfo.cpp lib/Target/TargetLibraryInfo.cpp
index ee88ce7..4fa6344 100644
--- lib/Target/TargetLibraryInfo.cpp
+++ lib/Target/TargetLibraryInfo.cpp
@@ -339,6 +339,8 @@ static void initialize(TargetLibraryInfo &TLI, const Triple &T,
       llvm_unreachable("TargetLibraryInfo function names must be sorted");
   }
 #endif // !NDEBUG
+
+  bool available;
   
   // memset_pattern16 is only available on iOS 3.0 and Mac OS/X 10.5 and later.
   if (T.isMacOSX()) {
@@ -528,34 +530,71 @@ static void initialize(TargetLibraryInfo &TLI, const Triple &T,
   }
 
   // ffsl is available on at least Darwin, Mac OS X, iOS, FreeBSD, and
-  // Linux (GLIBC):
+  // systems using glibc:
   // http://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man3/ffsl.3.html
   // http://svn.freebsd.org/base/user/eri/pf45/head/lib/libc/string/ffsl.c
   // http://www.gnu.org/software/gnulib/manual/html_node/ffsl.html
-  switch (T.getOS()) {
-  case Triple::Darwin:
-  case Triple::MacOSX:
-  case Triple::IOS:
-  case Triple::FreeBSD:
-  case Triple::Linux:
+  available = false;
+  switch (T.getEnvironment()) {
+  case Triple::GNU:
+    available = true;
     break;
   default:
-    TLI.setUnavailable(LibFunc::ffsl);
+    switch (T.getOS()) {
+    case Triple::Darwin:
+    case Triple::MacOSX:
+    case Triple::IOS:
+    case Triple::FreeBSD:
+    case Triple::Linux:
+      available = true;
+      break;
+    default:
+      break;
+    }
+    break;
   }
+  if (!available)
+    TLI.setUnavailable(LibFunc::ffsl);
 
-  // ffsll is available on at least FreeBSD and Linux (GLIBC):
+  // ffsll is available on at least FreeBSD and systems using glibc:
   // http://svn.freebsd.org/base/user/eri/pf45/head/lib/libc/string/ffsll.c
   // http://www.gnu.org/software/gnulib/manual/html_node/ffsll.html
-  switch (T.getOS()) {
-  case Triple::FreeBSD:
-  case Triple::Linux:
+  available = false;
+  switch (T.getEnvironment()) {
+  case Triple::GNU:
+    available = true;
     break;
   default:
-    TLI.setUnavailable(LibFunc::ffsll);
+    switch (T.getOS()) {
+    case Triple::FreeBSD:
+    case Triple::Linux:
+      available = true;
+      break;
+    default:
+      break;
+    }
+    break;
   }
+  if (!available)
+    TLI.setUnavailable(LibFunc::ffsll);
 
-  // The following functions are available on at least Linux:
-  if (T.getOS() != Triple::Linux) {
+  // The following functions are available on at least systems using glibc:
+  available = false;
+  switch (T.getEnvironment()) {
+  case Triple::GNU:
+    available = true;
+    break;
+  default:
+    switch (T.getOS()) {
+    case Triple::Linux:
+      available = true;
+      break;
+    default:
+      break;
+    }
+    break;
+  }
+  if (!available) {
     TLI.setUnavailable(LibFunc::dunder_strdup);
     TLI.setUnavailable(LibFunc::dunder_strtok_r);
     TLI.setUnavailable(LibFunc::dunder_isoc99_scanf);
-- 
1.7.9.5