[AST] Fix -ast-print for _Bool when have diagnostics
For example, given:
#define bool _Bool
_Bool i;
void fn() { 1; }
-ast-print produced:
tmp.c:3:13: warning: expression result unused
void fn() { 1; }
^
bool i;
void fn() {
1;
}
That fails to compile because bool is undefined.
Details:
Diagnostics print _Bool as bool when the latter is defined as the
former. However, diagnostics were altering the printing policy for
-ast-print as well. The printed source was then invalid because the
preprocessor eats the bool definition.
Problematic diagnostics included suppressed warnings (e.g., add
-Wno-unused-value to the above example), including those that are
suppressed by default.
This patch fixes this bug and cleans up some related comments.
Reviewed by: aaron.ballman, rsmith
Differential Revision: https://reviews.llvm.org/D45093
llvm-svn: 332275
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index eb336ee..c099768 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -52,8 +52,8 @@
PrintingPolicy Sema::getPrintingPolicy(const ASTContext &Context,
const Preprocessor &PP) {
PrintingPolicy Policy = Context.getPrintingPolicy();
- // Our printing policy is copied over the ASTContext printing policy whenever
- // a diagnostic is emitted, so recompute it.
+ // In diagnostics, we print _Bool as bool if the latter is defined as the
+ // former.
Policy.Bool = Context.getLangOpts().Bool;
if (!Policy.Bool) {
if (const MacroInfo *BoolMacro = PP.getMacroInfo(Context.getBoolName())) {
@@ -1287,7 +1287,8 @@
}
}
- // Set up the context's printing policy based on our current state.
+ // Copy the diagnostic printing policy over the ASTContext printing policy.
+ // TODO: Stop doing that. See: https://reviews.llvm.org/D45093#1090292
Context.setPrintingPolicy(getPrintingPolicy());
// Emit the diagnostic.