Driver: Fix a parsing bug where some options were matched

incorrectly. I'm blanking on the smartest way to write this search,
but we should just do the right thing when we move to TableGen.
 - <rdar://problem/6761194> [driver] -Wextra-tokens isn't parsed
   correctly

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68525 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/OptTable.cpp b/lib/Driver/OptTable.cpp
index 15b121c45b1bc0ec361dc78b580e3621bbaeff44..cbbeea1974cbcf0925db6062f0384cb150ced244 100644 (file)
--- a/lib/Driver/OptTable.cpp
+++ b/lib/Driver/OptTable.cpp
@@ -230,19 +230,26 @@ Arg *OptTable::ParseOneArg(const InputArgList &Args, unsigned &Index) const {
   struct Info *Start = OptionInfos + FirstSearchableOption - 1;
   struct Info *End = OptionInfos + LastOption - 1;
 
-  // Find the first option which could be a prefix.
+  // Search for the first next option which could be a prefix.
   Start = std::lower_bound(Start, End, Str);
 
-  // Scan for first option which is a proper prefix.
-  for (; Start != End; ++Start)
-    if (memcmp(Str, Start->Name, strlen(Start->Name)) == 0)
-      break;
-
-  // Look for a match until we don't have a prefix.
+  // Options are stored in sorted order, with '\0' at the end of the
+  // alphabet. Since the only options which can accept a string must
+  // prefix it, we iteratively search for the next option which could
+  // be a prefix.
+  //
+  // FIXME: This is searching much more than necessary, but I am
+  // blanking on the simplest way to make it fast. We can solve this
+  // problem when we move to TableGen.
   for (; Start != End; ++Start) {
-    if (memcmp(Start->Name, Str, strlen(Start->Name)) != 0)
+    // Scan for first option which is a proper prefix.
+    for (; Start != End; ++Start)
+      if (memcmp(Str, Start->Name, strlen(Start->Name)) == 0)
+        break;
+    if (Start == End)
       break;
 
+    // See if this option matches.
     options::ID id = (options::ID) (Start - OptionInfos + 1);
     if (Arg *A = getOption(id)->accept(Args, Index))
       return A;

diff --git a/test/Driver/parsing.c b/test/Driver/parsing.c
index ed70949a01a02f3096dee42e25a22c80b354f66d..7b6444050d7d3ca66e554fff0ebeb5064686a5c6 100644 (file)
--- a/test/Driver/parsing.c
+++ b/test/Driver/parsing.c
@@ -15,6 +15,10 @@
 // RUN: not clang -sectalign 1 2 2> %t &&
 // RUN: grep "error: argument to '-sectalign' is missing (expected 3 values)" %t &&
 
+// Verify that search continues after find the first option.
+// RUN: clang -ccc-print-options -Wally 2> %t &&
+// RUN: grep 'Option 0 - Name: "-W", Values: {"ally"}' %t &&
+
 // RUN: true