From 3ad2167bbac8ae83b1e91305b105ab5287bdac55 Mon Sep 17 00:00:00 2001 From: Lewis Hyatt Date: Wed, 15 Jun 2022 18:06:53 -0400 Subject: c++: libcpp: Support raw strings with newlines in directives [PR55971] It's not currently possible to use a C++11 raw string containing a newline as part of the definition of a macro, or in any other preprocessing directive, such as: #define X R"(two lines)" #error R"(this error has two lines)" Add support for that by relaxing the conditions under which _cpp_get_fresh_line() refuses to get a new line. For the case of lexing a raw string, it's OK to do so as long as there is another line within the current buffer. The code in cpp_get_fresh_line() was refactored into a new function get_fresh_line_impl(), so that the new logic is applied only when processing a raw string and not any other times. libcpp/ChangeLog: PR preprocessor/55971 * lex.cc (get_fresh_line_impl): New function refactoring the code from... (_cpp_get_fresh_line): ...here. (lex_raw_string): Use the new version of get_fresh_line_impl() to support raw strings containing new lines when processing a directive. gcc/testsuite/ChangeLog: PR preprocessor/55971 * c-c++-common/raw-string-directive-1.c: New test. * c-c++-common/raw-string-directive-2.c: New test. gcc/c-family/ChangeLog: PR preprocessor/55971 * c-ppoutput.cc (adjust_for_newlines): Update comment. --- libcpp/lex.cc | 41 ++++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) (limited to 'libcpp/lex.cc') diff --git a/libcpp/lex.cc b/libcpp/lex.cc index cc12a52d..b110792 100644 --- a/libcpp/lex.cc +++ b/libcpp/lex.cc @@ -1076,6 +1076,9 @@ _cpp_clean_line (cpp_reader *pfile) buffer->next_line = s + 1; } +template +static bool get_fresh_line_impl (cpp_reader *pfile); + /* Return true if the trigraph indicated by NOTE should be warned about in a comment. */ static bool @@ -2695,9 +2698,8 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base) { pos--; pfile->buffer->cur = pos; - if (pfile->state.in_directive - || (pfile->state.parsing_args - && pfile->buffer->next_line >= pfile->buffer->rlimit)) + if ((pfile->state.in_directive || pfile->state.parsing_args) + && pfile->buffer->next_line >= pfile->buffer->rlimit) { cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc, 0, "unterminated raw string"); @@ -2712,7 +2714,7 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base) CPP_INCREMENT_LINE (pfile, 0); pfile->buffer->need_line = true; - if (!_cpp_get_fresh_line (pfile)) + if (!get_fresh_line_impl (pfile)) { /* We ran out of file and failed to get a line. */ location_t src_loc = token->src_loc; @@ -2724,8 +2726,15 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base) _cpp_release_buff (pfile, accum.first); cpp_error_with_line (pfile, CPP_DL_ERROR, src_loc, 0, "unterminated raw string"); - /* Now pop the buffer that _cpp_get_fresh_line did not. */ + + /* Now pop the buffer that get_fresh_line_impl() did not. Popping + is not safe if processing a directive, however this cannot + happen as we already checked above that a line would be + available, and get_fresh_line_impl() can't fail in this + case. */ + gcc_assert (!pfile->state.in_directive); _cpp_pop_buffer (pfile); + return; } @@ -3659,11 +3668,14 @@ _cpp_lex_token (cpp_reader *pfile) } /* Returns true if a fresh line has been loaded. */ -bool -_cpp_get_fresh_line (cpp_reader *pfile) +template +static bool +get_fresh_line_impl (cpp_reader *pfile) { - /* We can't get a new line until we leave the current directive. */ - if (pfile->state.in_directive) + /* We can't get a new line until we leave the current directive, unless we + are lexing a raw string, in which case it will be OK as long as we don't + pop the current buffer. */ + if (!lexing_raw_string && pfile->state.in_directive) return false; for (;;) @@ -3679,6 +3691,10 @@ _cpp_get_fresh_line (cpp_reader *pfile) return true; } + /* We can't change buffers until we leave the current directive. */ + if (lexing_raw_string && pfile->state.in_directive) + return false; + /* First, get out of parsing arguments state. */ if (pfile->state.parsing_args) return false; @@ -3706,6 +3722,13 @@ _cpp_get_fresh_line (cpp_reader *pfile) } } +bool +_cpp_get_fresh_line (cpp_reader *pfile) +{ + return get_fresh_line_impl (pfile); +} + + #define IF_NEXT_IS(CHAR, THEN_TYPE, ELSE_TYPE) \ do \ { \ -- cgit v1.1