modernize-use-using evaluates macros when constructing the replacement

[llvmbot]

Bugzilla Link	34412
Version	unspecified
OS	Linux
Blocks	#37846
Reporter	LLVM Bugzilla Contributor

Extended Description

Version of clang-tidy: 4.0
Check: modernize-use-using

// Before:

#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

typedef void(SomeMacro(SomeType)::*FunctionType)(float arg1, int arg2);

// After:

#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

using FunctionType = void (SomeType::*)(float, int); // evaluated macro instead of "SomeMacro(SomeType)"

[llvmbot]

Still reproducible on r311654:

$ cat q.cc
#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

typedef void(SomeMacro(SomeType)::FunctionType)(float arg1, int arg2);
$ clang_tidy -checks=-,modernize-use-using -fix q.cc -- -std=c++11
1 warning generated.
/tmp/q.cc:9:1: warning: use 'using' instead of 'typedef' [modernize-use-using]
typedef void(SomeMacro(SomeType)::FunctionType)(float arg1, int arg2);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
using FunctionType = void (SomeType::)(float, int)
/tmp/q.cc:9:1: note: FIX-IT applied suggested code changes
clang-tidy applied 1 of 1 suggested fixes.
$ cat q.cc
#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

using FunctionType = void (SomeType::*)(float, int);

I don't whether we can do anything beyond just disabling the fix in this case.

[PeterFeicht]

mentioned in issue #37846

[llvmbot]

@llvm/issue-subscribers-bug

Author: None (llvmbot)

| | | | --- | --- | | Bugzilla Link | [34412](https://llvm.org/bz34412) | | Version | unspecified | | OS | Linux | | Blocks | llvm/llvm-project#37846 | | Reporter | LLVM Bugzilla Contributor |

Extended Description

Version of clang-tidy: 4.0
Check: modernize-use-using

// Before:

#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

typedef void(SomeMacro(SomeType)::*FunctionType)(float arg1, int arg2);

// After:

#ifndef SpecialMode
#define SomeMacro(x) x
#else
#define SomeMacro(x) SpecialType
#endif

class SomeMacro(SomeType) { };

using FunctionType = void (SomeType::*)(float, int); // evaluated macro instead of "SomeMacro(SomeType)"