On 22/07/24 12:24 +0300, Ovidiu Panait wrote:
Hi,
When processing large header files, the C preprocessor reports error
on the wrong line.
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This is 100% reproducible on my side with gcc mainline.
Reproducer:
# Build
mkdir build; cd build
../configure --host=x86_64-pc-linux-gnu --target=x86_64-wrs-linux
--enable-languages=c --disable-multilib --disable-libstdcxx-pch
--disable-libsanitizer --disable-libssp --disable-libquadmath
--disable-libquadmath-support --disable-libgomp --disable-libvtv
--disable-bootstrap
make all-host -j$(nproc)
mkdir install; make install-host DESTDIR=$(realpath ./install) -j$(nproc)
# Generate testcase
mkdir testcase; cd testcase
cat > main.c <<EOF
extern int main_begins;
extern int main_begins;
extern int main_begins;
#include "header1.h"
EOF
echo -n > header1.h
for i in {1..327676}; do
echo "extern int header1_begins;" >> header1.h
done
cat >> header1.h <<EOF
#include "header2.h"
extern int header1 ends;
EOF
echo -n > header2.h
# Test
../install/usr/local/bin/x86_64-wrs-linux-gcc main.c
In file included from main.c:4:
header1.h:327677:20: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or
‘__attribute__’ before ‘ends’
327677 | #include "header2.h"
| ^
The line where the error is reported("327677") is bogus, the actual
error is on the next line("327678") in header1.h:
$ cat -n header1.h | tail -n3
327676 extern int header1_begins;
327677 #include "header2.h"
327678 extern int header1 ends;
Ovidiu
