https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96935
Bug ID: 96935
Summary: ICE in subspan, at input.h:69
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: preprocessor
Assignee: unassigned at gcc dot gnu.org
Reporter: jan.smets at nokia dot com
Target Milestone: ---
Following ICE is seen :
x.cpp: In function 'void a()':
x.cpp:3: internal compiler error: in subspan, at input.h:69
3 | #define DB_PRINTF(str, fmt, args...) db_printf(indent_len, 50, fmt,
str, ##args)
|
x.cpp:7: note: in expansion of macro 'DB_PRINTF'
7 | DB_PRINTF("", "%llu", 0);
|
Target: x86_64-linux-gnu
Configured with: /usr/src/gcc/configure --build=x86_64-linux-gnu
--disable-multilib --enable-languages=c,c++,fortran,go
Compiled with: -O2 -Wformat
Reproduces with
10.2, 10.1
9.3, 9.1
Works with
8.4
7.5
The reduced testcase is :
#include "x.h"
#define DB_PRINTF(str, fmt, args...) db_printf(indent_len, 50, fmt, str,
##args)
extern "C" void db_printf(unsigned indent_len, unsigned column_split, const
char * fmt, const char * str, ...) __attribute__ ((format (printf, 3, 5)));
void a() {
unsigned int indent_len = 0;
DB_PRINTF("", "%llu", 0);
// preprocesses to: db_printf(indent_len, 50, "%llu", "");
}
But I suspect the testcase is just garbage.
I tried various ways trying to reduce x.h, but even the slightest change makes
the problem go away. "x.h" recursively includes about 200 other header files.
A "flat" x.h (700k lines) (-fdirectives-only) does not reproduce the issue.
This ICE occurs on couple of dozen files in my project. Some print
"during GIMPLE pass: strlen".
Goes away with --enable-checking=no, but then other problems show up (ICE in
linemap_compare_locations, at libcpp/line-map.c:1359 - which may or may not be
related)
I suppose my next best option is start a bisect between 8.x and 9.x ?
Thanks
