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Fix #368 (__VA_OPT__ is not handled good enough) #451

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Merged
danmar merged 9 commits into from
Jul 1, 2025
Merged

Fix #368 (__VA_OPT__ is not handled good enough) #451

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9fd5f63
Fix __VA_OPT__ handling
glankk Jun 30, 2025
8922368
Fix handling of empty variadic parameters, add test
glankk Jun 30, 2025
2a41f27
Add test case for empty parameter list
glankk Jun 30, 2025
36dc794
Nicer tests
glankk Jun 30, 2025
3272f6f
Fix location report for missing closing parenthesis
glankk Jun 30, 2025
448a22e
Fix expected test value
glankk Jun 30, 2025
173443b
Add test case for eof in __VA_OPT__
glankk Jul 1, 2025
8c7287d
Fix typo
glankk Jul 1, 2025
760532c
Add macro name for __VA_OPT__ syntax errors
glankk Jul 1, 2025
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111 changes: 89 additions & 22 deletions simplecpp.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1485,7 +1485,7 @@ namespace simplecpp {

class Macro {
public:
explicit Macro(std::vector<std::string> &f) : nameTokDef(nullptr), valueToken(nullptr), endToken(nullptr), files(f), tokenListDefine(f), variadic(false), valueDefinedInCode_(false) {}
explicit Macro(std::vector<std::string> &f) : nameTokDef(nullptr), valueToken(nullptr), endToken(nullptr), files(f), tokenListDefine(f), variadic(false), variadicOpt(false), optExpandValue(nullptr), optNoExpandValue(nullptr), valueDefinedInCode_(false) {}

Macro(const Token *tok, std::vector<std::string> &f) : nameTokDef(nullptr), files(f), tokenListDefine(f), valueDefinedInCode_(true) {
if (sameline(tok->previousSkipComments(), tok))
Expand Down Expand Up @@ -1515,6 +1515,11 @@ namespace simplecpp {
*this = other;
}

~Macro() {
delete optExpandValue;
delete optNoExpandValue;
}

Macro &operator=(const Macro &other) {
if (this != &other) {
files = other.files;
Expand Down Expand Up @@ -1707,6 +1712,9 @@ namespace simplecpp {
bool parseDefine(const Token *nametoken) {
nameTokDef = nametoken;
variadic = false;
variadicOpt = false;
optExpandValue = nullptr;
optNoExpandValue = nullptr;
if (!nameTokDef) {
valueToken = endToken = nullptr;
args.clear();
Expand Down Expand Up @@ -1744,8 +1752,54 @@ namespace simplecpp {
if (!sameline(valueToken, nameTokDef))
valueToken = nullptr;
endToken = valueToken;
while (sameline(endToken, nameTokDef))
while (sameline(endToken, nameTokDef)) {
if (variadic && endToken->str() == "__VA_OPT__")
variadicOpt = true;
endToken = endToken->next;
}

if (variadicOpt) {
TokenList expandValue(files);
TokenList noExpandValue(files);
for (const Token *tok = valueToken; tok && tok != endToken;) {
if (tok->str() == "__VA_OPT__") {
if (!sameline(tok, tok->next) || tok->next->op != '(')
throw Error(tok->location, "Missing opening parenthesis for __VA_OPT__");
tok = tok->next->next;
int par = 1;
while (tok && tok != endToken) {
if (tok->op == '(')
par++;
else if (tok->op == ')')
par--;
else if (tok->str() == "__VA_OPT__")
throw Error(tok->location, "__VA_OPT__ cannot be nested");
if (par == 0) {
tok = tok->next;
break;
}
expandValue.push_back(new Token(*tok));
tok = tok->next;
}
if (par != 0) {
const Token *const lastTok = expandValue.back() ? expandValue.back() : valueToken->next;
throw Error(lastTok->location, "Missing closing parenthesis for __VA_OPT__");
}
} else {
expandValue.push_back(new Token(*tok));
noExpandValue.push_back(new Token(*tok));
tok = tok->next;
}
}
#if __cplusplus >= 201103L
optExpandValue = new TokenList(std::move(expandValue));
optNoExpandValue = new TokenList(std::move(noExpandValue));
#else
optExpandValue = new TokenList(expandValue);
optNoExpandValue = new TokenList(noExpandValue);
#endif
}

return true;
}

Expand Down Expand Up @@ -1900,8 +1954,22 @@ namespace simplecpp {

Token * const output_end_1 = output->back();

const Token *valueToken2;
const Token *endToken2;

if (variadicOpt) {
if (parametertokens2.size() > args.size() && parametertokens2[args.size() - 1]->next->op != ')')
valueToken2 = optExpandValue->cfront();
else
valueToken2 = optNoExpandValue->cfront();
endToken2 = nullptr;
} else {
valueToken2 = valueToken;
endToken2 = endToken;
}

// expand
for (const Token *tok = valueToken; tok != endToken;) {
for (const Token *tok = valueToken2; tok != endToken2;) {
if (tok->op != '#') {
// A##B => AB
if (sameline(tok, tok->next) && tok->next && tok->next->op == '#' && tok->next->next && tok->next->next->op == '#') {
Expand Down Expand Up @@ -1950,7 +2018,7 @@ namespace simplecpp {
}

tok = tok->next;
if (tok == endToken) {
if (tok == endToken2) {
output->push_back(new Token(*tok->previous));
break;
}
Expand Down Expand Up @@ -2020,24 +2088,6 @@ namespace simplecpp {
// Macro parameter..
{
TokenList temp(files);
if (tok->str() == "__VA_OPT__") {
if (sameline(tok, tok->next) && tok->next->str() == "(") {
tok = tok->next;
int paren = 1;
while (sameline(tok, tok->next)) {
if (tok->next->str() == "(")
++paren;
else if (tok->next->str() == ")")
--paren;
if (paren == 0)
return tok->next->next;
tok = tok->next;
if (parametertokens.size() > args.size() && parametertokens.front()->next->str() != ")")
tok = expandToken(output, loc, tok, macros, expandedmacros, parametertokens)->previous;
}
}
throw Error(tok->location, "Missing parenthesis for __VA_OPT__(content)");
}
if (expandArg(&temp, tok, loc, macros, expandedmacros, parametertokens)) {
if (tok->str() == "__VA_ARGS__" && temp.empty() && output->cback() && output->cback()->str() == "," &&
tok->nextSkipComments() && tok->nextSkipComments()->str() == ")")
Expand Down Expand Up @@ -2338,6 +2388,13 @@ namespace simplecpp {
/** is macro variadic? */
bool variadic;

/** does the macro expansion have __VA_OPT__? */
bool variadicOpt;

/** Expansion value for varadic macros with __VA_OPT__ expanded and discarded respecively */
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const TokenList *optExpandValue;
const TokenList *optNoExpandValue;

/** was the value of this macro actually defined in the code? */
bool valueDefinedInCode_;
};
Expand Down Expand Up @@ -3621,6 +3678,16 @@ void simplecpp::preprocess(simplecpp::TokenList &output, const simplecpp::TokenL
}
output.clear();
return;
} catch (simplecpp::Macro::Error &err) {
if (outputList) {
simplecpp::Output out(files);
out.type = simplecpp::Output::SYNTAX_ERROR;
out.location = err.location;
out.msg = "Failed to parse #define, " + err.what;
outputList->push_back(out);
}
output.clear();
return;
}
} else if (ifstates.top() == True && rawtok->str() == INCLUDE) {
TokenList inc1(files);
Expand Down
51 changes: 46 additions & 5 deletions test.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -923,7 +923,7 @@ static void define_va_opt_3()

simplecpp::OutputList outputList;
ASSERT_EQUALS("", preprocess(code1, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,failed to expand 'err', Missing parenthesis for __VA_OPT__(content)\n",
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing closing parenthesis for __VA_OPT__\n",
toString(outputList));

outputList.clear();
Expand All @@ -934,7 +934,7 @@ static void define_va_opt_3()
"err()";

ASSERT_EQUALS("", preprocess(code2, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,failed to expand 'err', Missing parenthesis for __VA_OPT__(content)\n",
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing opening parenthesis for __VA_OPT__\n",
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toString(outputList));
}

Expand All @@ -946,7 +946,7 @@ static void define_va_opt_4()

simplecpp::OutputList outputList;
ASSERT_EQUALS("", preprocess(code1, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,failed to expand 'err', Missing parenthesis for __VA_OPT__(content)\n",
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing opening parenthesis for __VA_OPT__\n",
toString(outputList));

outputList.clear();
Expand All @@ -956,7 +956,7 @@ static void define_va_opt_4()
"err()";

ASSERT_EQUALS("", preprocess(code2, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,failed to expand 'err', Missing parenthesis for __VA_OPT__(content)\n",
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing opening parenthesis for __VA_OPT__\n",
toString(outputList));
}

Expand All @@ -968,7 +968,46 @@ static void define_va_opt_5()

simplecpp::OutputList outputList;
ASSERT_EQUALS("", preprocess(code, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,failed to expand 'err', Missing parenthesis for __VA_OPT__(content)\n",
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing opening parenthesis for __VA_OPT__\n",
toString(outputList));
}

static void define_va_opt_6()
{
// nested __VA_OPT__
const char code[] = "#define err(...) __VA_OPT__(__VA_OPT__(something))\n"
"err()";

simplecpp::OutputList outputList;
ASSERT_EQUALS("", preprocess(code, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, __VA_OPT__ cannot be nested\n",
toString(outputList));
}

static void define_va_opt_7()
{
// eof in __VA_OPT__
const char code1[] = "#define err(...) __VA_OPT__";

simplecpp::OutputList outputList;
ASSERT_EQUALS("", preprocess(code1, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing opening parenthesis for __VA_OPT__\n",
toString(outputList));

outputList.clear();

const char code2[] = "#define err(...) __VA_OPT__(";

ASSERT_EQUALS("", preprocess(code2, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing closing parenthesis for __VA_OPT__\n",
toString(outputList));

outputList.clear();

const char code3[] = "#define err(...) __VA_OPT__(x";

ASSERT_EQUALS("", preprocess(code3, &outputList));
ASSERT_EQUALS("file0,1,syntax_error,Failed to parse #define, Missing closing parenthesis for __VA_OPT__\n",
toString(outputList));
}

Expand Down Expand Up @@ -3063,6 +3102,8 @@ int main(int argc, char **argv)
TEST_CASE(define_va_opt_3);
TEST_CASE(define_va_opt_4);
TEST_CASE(define_va_opt_5);
TEST_CASE(define_va_opt_6);
TEST_CASE(define_va_opt_7);

TEST_CASE(pragma_backslash); // multiline pragma directive

Expand Down
13 changes: 13 additions & 0 deletions testsuite/clang-preprocessor-tests/macro_fn_va_opt.c
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Original file line number Diff line number Diff line change
@@ -0,0 +1,13 @@
// RUN: %clang_cc1 -E %s | grep '^ printf( "%%s" , "Hello" );$'

#define P( x, ...) printf( x __VA_OPT__(,) __VA_ARGS__ )
#define PF( x, ...) P( x __VA_OPT__(,) __VA_ARGS__ )

int main()
{
PF( "%s", "Hello" );
PF( "Hello", );
PF( "Hello" );
PF( , );
PF( );
}
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