| Message ID | 501C0D4A.1070906@codesourcery.com |
|---|---|
| State | New |
| Headers | show |
Sandra Loosemore <sandra@codesourcery.com> writes: > For all supported MIPS ABIs other than EABI, compiling with > -fpic/-fPIC/-fpie/-fPIE implicitly requires abicalls support. On Linux > targets, -mabicalls is the default, but bare-metal targets like > mips-sde-elf default to -mno-abicalls and naively compiling with -fPIC > alone doesn't result in working code. (In fact, even "-fPIC -mabicalls" > doesn't work, because -mabicalls then conflicts with the default for -G, > and the linker rejects mixing -mabicalls code with -mno-abicalls > libraries.) Yeah. I was tempted to add a message for this a while back, but I think there was resistance from someone who was managing to generate a form of PIC with careful use of that combination. If they did, it was by accident rather than design. However, EABI doesn't support PIC at all. (There used to be an -membedded-pic option, but that's long gone.) So I think this: > Index: gcc/config/mips/mips.c > =================================================================== > --- gcc/config/mips/mips.c (revision 190052) > +++ gcc/config/mips/mips.c (working copy) > @@ -15872,6 +15872,8 @@ static void > mips_option_override (void) > { > int i, start, regno, mode; > + static const char * const mips_abi_name[] = > + {"-mabi=32", "-mabi=n32", "-mabi=64", "-mabi=eabi", "-mabi=o64"}; > > if (global_options_set.x_mips_isa_option) > mips_isa_option_info = &mips_cpu_info_table[mips_isa_option]; > @@ -16053,6 +16055,12 @@ mips_option_override (void) > target_flags &= ~MASK_ABICALLS; > } > > + /* On non-EABI targets, -fpic and -fpie require -mabicalls. */ > + if (mips_abi != ABI_EABI && (flag_pic || flag_pie) && !TARGET_ABICALLS) > + error ("the combination of %qs and %qs is incompatible with %qs", > + (flag_pic ? "-fpic" : "-fpie"), > + "-mno-abicalls", mips_abi_name[mips_abi]); should be: if (flag_pic) { if (mips_abi == ABI_EABI) error ("cannot generate position-independent code for %qs", "-mabi=eabi"); else if (!TARGET_ABICALLS) error ("position-independent code requires %qs", "-mabicalls"); } (where flag_pie implies flag_pic). I've removed the -fpic/-fpie thing to avoid having to decide between printing "-fpic" and "-fPIC" (or "-fpie" and "-fPIE"). OK with that change, if you agree. Richard
Index: gcc/config/mips/mips.c =================================================================== --- gcc/config/mips/mips.c (revision 190052) +++ gcc/config/mips/mips.c (working copy) @@ -15872,6 +15872,8 @@ static void mips_option_override (void) { int i, start, regno, mode; + static const char * const mips_abi_name[] = + {"-mabi=32", "-mabi=n32", "-mabi=64", "-mabi=eabi", "-mabi=o64"}; if (global_options_set.x_mips_isa_option) mips_isa_option_info = &mips_cpu_info_table[mips_isa_option]; @@ -16053,6 +16055,12 @@ mips_option_override (void) target_flags &= ~MASK_ABICALLS; } + /* On non-EABI targets, -fpic and -fpie require -mabicalls. */ + if (mips_abi != ABI_EABI && (flag_pic || flag_pie) && !TARGET_ABICALLS) + error ("the combination of %qs and %qs is incompatible with %qs", + (flag_pic ? "-fpic" : "-fpie"), + "-mno-abicalls", mips_abi_name[mips_abi]); + if (TARGET_ABICALLS_PIC2) /* We need to set flag_pic for executables as well as DSOs because we may reference symbols that are not defined in Index: gcc/testsuite/g++.dg/opt/enum2.C =================================================================== --- gcc/testsuite/g++.dg/opt/enum2.C (revision 190052) +++ gcc/testsuite/g++.dg/opt/enum2.C (working copy) @@ -1,8 +1,8 @@ // PR c++/43680 // Test that we don't make excessively aggressive assumptions about what // values an enum variable can have. +// { dg-do run { target fpic } } // { dg-options "-O2 -fPIC" } -// { dg-do run } extern "C" void abort (); Index: gcc/testsuite/g++.dg/lto/20090303_0.C =================================================================== --- gcc/testsuite/g++.dg/lto/20090303_0.C (revision 190052) +++ gcc/testsuite/g++.dg/lto/20090303_0.C (working copy) @@ -1,4 +1,5 @@ /* { dg-lto-do run } */ +/* { dg-require-effective-target fpic } */ /* { dg-lto-options {{-flto -flto-partition=1to1 -fPIC}} } */ /* { dg-lto-options {{-flto -flto-partition=1to1}} { target sparc*-*-* } } */ /* { dg-suppress-ld-options {-fPIC} } */