Re: [Tinycc-devel] Bug that TinyCC Analyses Strings inside #if 0 blocks

[Vincent Lefevre]

On 2022-07-11 17:47:31 +0200, Domingo Alvarez Duarte wrote:
> Although gcc compiles a file containing your example with warnings, I'm not
> sure it's worth try to do the same in TiinyCC the preprocessor probably uses
> TOKENS from the lexer to decide to skip till the end of the initial "#if 0"
> and '"' is not a valid token the error probably come from the lexer that
> found a non terminated string.

I agree that tcc should reject the code. It is too ambiguous to be
regarded as an extension. GCC's interpretation is rather ugly.

Consider a file "err.c":

#define FOO bar
"
FOO
"
"FOO"

zira:~> gcc -E err.c 2> /dev/null
# 0 "err.c"
# 0 "<built-in>"
# 0 "<command-line>"
# 1 "/usr/include/stdc-predef.h" 1 3 4
# 0 "<command-line>" 2
# 1 "err.c"

"
bar
"
"FOO"

while with tcc:

zira:~> tcc -E err.c
# 1 "err.c"
# 1 "<command line>" 1
# 2 "err.c" 2


"
FOO
"
"FOO"

which makes more sense as an extension, IMHO. But tcc doesn't give
any diagnostic there, and I think that this is incorrect.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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