[llvm] r252531 - Combine ifdefs around dl_iterate_phdr in Unix/Signals.inc

[Reid Kleckner via llvm-commits]

Author: rnk
Date: Mon Nov  9 17:10:29 2015
New Revision: 252531

URL: http://llvm.org/viewvc/llvm-project?rev=252531&view=rev
Log:
Combine ifdefs around dl_iterate_phdr in Unix/Signals.inc

This avoids the need to have two dummy implementations of
findModulesAndOffsets.

Modified:
    llvm/trunk/lib/Support/Unix/Signals.inc

Modified: llvm/trunk/lib/Support/Unix/Signals.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Unix/Signals.inc?rev=252531&r1=252530&r2=252531&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Unix/Signals.inc (original)
+++ llvm/trunk/lib/Support/Unix/Signals.inc Mon Nov  9 17:10:29 2015
@@ -253,10 +253,9 @@ void llvm::sys::AddSignalHandler(void (*
   RegisterHandlers();
 }
 
-#if defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES)
-
-#if HAVE_LINK_H && (defined(__linux__) || defined(__FreeBSD__) ||              \
-                    defined(__FreeBSD_kernel__) || defined(__NetBSD__))
+#if defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES) && HAVE_LINK_H &&    \
+    (defined(__linux__) || defined(__FreeBSD__) ||                             \
+     defined(__FreeBSD_kernel__) || defined(__NetBSD__))
 struct DlIteratePhdrData {
   void **StackTrace;
   int depth;
@@ -289,6 +288,8 @@ static int dl_iterate_phdr_cb(dl_phdr_in
   return 0;
 }
 
+/// If this is an ELF platform, we can find all loaded modules and their virtual
+/// addresses with dl_iterate_phdr.
 static bool findModulesAndOffsets(void **StackTrace, int Depth,
                                   const char **Modules, intptr_t *Offsets,
                                   const char *MainExecutableName,
@@ -299,21 +300,15 @@ static bool findModulesAndOffsets(void *
   return true;
 }
 #else
+/// This platform does not have dl_iterate_phdr, so we do not yet know how to
+/// find all loaded DSOs.
 static bool findModulesAndOffsets(void **StackTrace, int Depth,
                                   const char **Modules, intptr_t *Offsets,
                                   const char *MainExecutableName,
                                   StringSaver &StrPool) {
   return false;
 }
-#endif
-#else
-static bool findModulesAndOffsets(void **StackTrace, int Depth,
-                                  const char **Modules, intptr_t *Offsets,
-                                  const char *MainExecutableName,
-                                  StringSaver &StrPool) {
-  return false;
-}
-#endif // defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES)
+#endif // defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES) && ...
 
 // PrintStackTrace - In the case of a program crash or fault, print out a stack
 // trace so that the user has an indication of why and where we died.