Handle -D arguments ending in a backslash.
We translate these into #define directives; to preserve gcc-compatible
semantics (where the expanded macro includes the backslash), we add
an extra "\\\n" to the end of the synthesized "#define".
<rdar://problem/14810220>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189511 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/InitPreprocessor.cpp b/lib/Frontend/InitPreprocessor.cpp
index dc3ab53..2eb74e0 100644
--- a/lib/Frontend/InitPreprocessor.cpp
+++ b/lib/Frontend/InitPreprocessor.cpp
@@ -29,6 +29,12 @@
#include "llvm/Support/Path.h"
using namespace clang;
+static bool MacroBodyEndsInBackslash(StringRef MacroBody) {
+ while (!MacroBody.empty() && isWhitespace(MacroBody.back()))
+ MacroBody = MacroBody.drop_back();
+ return !MacroBody.empty() && MacroBody.back() == '\\';
+}
+
// Append a #define line to Buf for Macro. Macro should be of the form XXX,
// in which case we emit "#define XXX 1" or "XXX=Y z W" in which case we emit
// "#define XXX Y z W". To get a #define with no value, use "XXX=".
@@ -43,7 +49,14 @@
if (End != StringRef::npos)
Diags.Report(diag::warn_fe_macro_contains_embedded_newline)
<< MacroName;
- Builder.defineMacro(MacroName, MacroBody.substr(0, End));
+ MacroBody = MacroBody.substr(0, End);
+ // We handle macro bodies which end in a backslash by appending an extra
+ // backslash+newline. This makes sure we don't accidentally treat the
+ // backslash as a line continuation marker.
+ if (MacroBodyEndsInBackslash(MacroBody))
+ Builder.defineMacro(MacroName, Twine(MacroBody) + "\\\n");
+ else
+ Builder.defineMacro(MacroName, MacroBody);
} else {
// Push "macroname 1".
Builder.defineMacro(Macro);