[clang] 822c274 - [clang-cl] Ignore #pragma managed/unmanaged

[Sylvain Audi via cfe-commits]

Author: Sylvain Audi
Date: 2022-12-12T10:01:24-05:00
New Revision: 822c274477ea2f194b4e3f2a38fdb3d3ba8ea611

URL: https://github.com/llvm/llvm-project/commit/822c274477ea2f194b4e3f2a38fdb3d3ba8ea611
DIFF: https://github.com/llvm/llvm-project/commit/822c274477ea2f194b4e3f2a38fdb3d3ba8ea611.diff

LOG: [clang-cl] Ignore #pragma managed/unmanaged

Those 2 pragmas are ignored by MSVC when not compiling with /CLR, which clang doesn't support.
Ignore them in clang -fms-extensions, to avoid -Wunknown-pragma warnings

Differential Revision: https://reviews.llvm.org/D139632

Added: 
    

Modified: 
    clang/lib/Lex/Pragma.cpp
    clang/test/Preprocessor/pragma_microsoft.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index 747447e3ab39a..01e0dbe05ac96 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -1957,6 +1957,15 @@ struct PragmaRegionHandler : public PragmaHandler {
   }
 };
 
+/// "\#pragma managed"
+/// "\#pragma managed(...)"
+/// "\#pragma unmanaged"
+/// MSVC ignores this pragma when not compiling using /clr, which clang doesn't
+/// support. We parse it and ignore it to avoid -Wunknown-pragma warnings.
+struct PragmaManagedHandler : public EmptyPragmaHandler {
+  PragmaManagedHandler(const char *pragma) : EmptyPragmaHandler(pragma) {}
+};
+
 /// This handles parsing pragmas that take a macro name and optional message
 static IdentifierInfo *HandleMacroAnnotationPragma(Preprocessor &PP, Token &Tok,
                                                    const char *Pragma,
@@ -2129,6 +2138,8 @@ void Preprocessor::RegisterBuiltinPragmas() {
     AddPragmaHandler(new PragmaIncludeAliasHandler());
     AddPragmaHandler(new PragmaHdrstopHandler());
     AddPragmaHandler(new PragmaSystemHeaderHandler());
+    AddPragmaHandler(new PragmaManagedHandler("managed"));
+    AddPragmaHandler(new PragmaManagedHandler("unmanaged"));
   }
 
   // Pragmas added by plugins

diff  --git a/clang/test/Preprocessor/pragma_microsoft.c b/clang/test/Preprocessor/pragma_microsoft.c
index aae6e284cb4dc..afbe0ebc8f19d 100644
--- a/clang/test/Preprocessor/pragma_microsoft.c
+++ b/clang/test/Preprocessor/pragma_microsoft.c
@@ -235,6 +235,12 @@ void pragma_optimize_foo() {
 #pragma optimize("", on) // expected-error {{'#pragma optimize' can only appear at file scope}}
 }
 
+#pragma managed            // no-warning
+#pragma unmanaged          // no-warning
+#pragma managed(push, on)  // no-warning
+#pragma managed(pop)       // no-warning
+#pragma managed2           // expected-warning{{unknown pragma ignored}}
+
 #pragma execution_character_set                 // expected-warning {{expected '('}}
 #pragma execution_character_set(                // expected-warning {{expected 'push' or 'pop'}}
 #pragma execution_character_set()               // expected-warning {{expected 'push' or 'pop'}}