[ADT] Normalize empty triple components
LLVM triple normalization is handling "unknown" and empty components
differently; for example given "x86_64-unknown-linux-gnu" and
"x86_64-linux-gnu" which should be equivalent, triple normalization
returns "x86_64-unknown-linux-gnu" and "x86_64--linux-gnu". autoconf's
config.sub returns "x86_64-unknown-linux-gnu" for both
"x86_64-linux-gnu" and "x86_64-unknown-linux-gnu". This changes the
triple normalization to behave the same way, replacing empty triple
components with "unknown".
This addresses PR37129.
Differential Revision: https://reviews.llvm.org/D50219
llvm-svn: 339294
diff --git a/llvm/lib/Support/Triple.cpp b/llvm/lib/Support/Triple.cpp
index b14d649..c48be2d 100644
--- a/llvm/lib/Support/Triple.cpp
+++ b/llvm/lib/Support/Triple.cpp
@@ -887,6 +887,12 @@
}
}
+ // Replace empty components with "unknown" value.
+ for (unsigned i = 0, e = Components.size(); i < e; ++i) {
+ if (Components[i].empty())
+ Components[i] = "unknown";
+ }
+
// Special case logic goes here. At this point Arch, Vendor and OS have the
// correct values for the computed components.
std::string NormalizedEnvironment;