initify plugin crashes on arm allmodconfig

From: Arnd Bergmann
Date: Wed Feb 01 2017 - 08:53:40 EST


On my ARM test builds (using a recent gcc-7 snapshot), allmodconfig failed with a compiler
crash, I have managed to minimize the test case to this:

/home/arnd/cross-gcc/bin/arm-linux-gnueabi-gcc-7.0.1 -O2 -Wall -fplugin=/home/arnd/arm-soc/build/tmp/scripts/gcc-plugins/initify_plugin.so -DINITIFY_PLUGIN -fplugin-arg-initify_plugin-search_init_exit_functions -fno-inline-functions-called-once -S atmel_lcdfb.i
arm-linux-gnueabi-gcc-7.0.1: internal compiler error: Segmentation fault (program cc1)

struct {
void *par;
} * c, g;
struct atmel_lcdfb_pdata {
void (*atmel_lcdfb_power_control)();
};
int a, f;
void *d, *e;
int fn1();
inline void fn2(int *p1) {
struct atmel_lcdfb_pdata *b = b;
if (b)
b->atmel_lcdfb_power_control();
a = fn1();
}
int __attribute__((__section__(".init.text"))) fn3() {
if (c)
goto out;
if (f)
goto free_info;
if (0)
goto put_bus_clk;
if (0)
goto release_intmem;
if (0)
goto stop_clk;
if (0)
goto free_fb;
if (e)
goto release_mem;
if (f)
goto unmap_mmio;
if (0)
goto unregister_irqs;
if (0)
goto reset_drvdata;
fn2(d);
reset_drvdata:
unregister_irqs:
unmap_mmio:
release_mem:
free_fb:
release_intmem:
stop_clk:
put_bus_clk:
free_info:
out:
return 0;
}
int __attribute__((__section__(".exit.text"))) __attribute__((__cold__)) fn4() {
fn2(g.par);
return 0;
}


While trying to reproduce it, one time I ended up killing the gcc task when it
used more than 80 gigabytes (!) of memory after around six minutes of compiling
the same file (drivers/video/fbdev/atmel_lcdfb.c), but other times it just crashed
as above using various ARM cross compilers (4.9.3, 5.3, 6.1.1).

Arnd