[ELF] - Teach linkerscript error handler to show full script line and column marker on error.
When error, this adds the text line of script to the output
and a marks exact incorrect token under it:
line 1: <error text here>
UNKNOWN_TAG {
^
Differential revision: http://reviews.llvm.org/D18699
llvm-svn: 265523
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index abd8d0a..36c9252 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -138,6 +138,7 @@
void readSectionPatterns(StringRef OutSec, bool Keep);
size_t getPos();
+ void printErrorPos();
std::vector<uint8_t> parseHex(StringRef S);
StringSaver Saver;
@@ -172,11 +173,31 @@
}
}
+// Returns the line that the character S[Pos] is in.
+static StringRef getLine(StringRef S, size_t Pos) {
+ size_t Begin = S.rfind('\n', Pos);
+ size_t End = S.find('\n', Pos);
+ Begin = (Begin == StringRef::npos) ? 0 : Begin + 1;
+ if (End == StringRef::npos)
+ End = S.size();
+ // rtrim for DOS-style newlines.
+ return S.substr(Begin, End - Begin).rtrim();
+}
+
+void ScriptParser::printErrorPos() {
+ StringRef Tok = Tokens[Pos == 0 ? 0 : Pos - 1];
+ StringRef Line = getLine(Input, Tok.data() - Input.data());
+ size_t Col = Tok.data() - Line.data();
+ error(Line);
+ error(std::string(Col, ' ') + "^");
+}
+
// We don't want to record cascading errors. Keep only the first one.
void ScriptParser::setError(const Twine &Msg) {
if (Error)
return;
error("line " + Twine(getPos()) + ": " + Msg);
+ printErrorPos();
Error = true;
}