Alberto Donizetti e99dafc4a8 cmd/compile: fix misleading "truncated to int" messages ... When defining an int const, the compiler tries to cast the RHS expression to int. The cast may fail for three reasons: 1. expr is an integer constant that overflows int 2. expr is a floating point constant 3. expr is a complex constant, or not a number In the second case, in order to print a sensible error message, we must distinguish between a floating point constant that should be included in the error message and a floating point constant that cannot be reasonably formatted for inclusion in an error message. For example, in: const a int = 1.1 const b int = 1 + 1e-100 a is in the former group, while b is in the latter, since the floating point value resulting from the evaluation of the rhs of the assignment (1.00...01) is too long to be fully printed in an error message, and cannot be shortened without making the error message misleading (rounding or truncating it would result in a "1", which looks like an integer constant, and it makes little sense in an error message about an invalid floating point expression). To fix this problem, we try to format the float value using fconv (which is used by the error reporting mechanism to format float arguments), and then parse the resulting string back to a big.Float. If the result is an integer, we assume that expr is a float value that cannot be reasonably be formatted as a string, and we emit an error message that does not include its string representation. Also, change the error message for overflows to a more conservative "integer too large", which does not mention overflows that are only caused by an internal implementation restriction. Also, change (*Mpint) SetFloat so that it returns a bool (instead of 0/-1 for success/failure). Fixes #11371 Change-Id: Ibbc73e2ed2eaf41f07827b0649d0eb637150ecaa Reviewed-on: https://go-review.googlesource.com/35411 Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com> Run-TryBot: Robert Griesemer <gri@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>		2017-03-07 19:34:22 +00:00
..
alias3.dir	[dev.typealias] cmd/compile: export/import test cases for type aliases	2017-01-20 05:55:53 +00:00
bench	test/bench/go1: reduce fasta data size for mips{,64}	2016-12-13 22:04:23 +00:00
chan
ddd2.dir
dwarf
fixedbugs	cmd/compile: fix misleading "truncated to int" messages	2017-03-07 19:34:22 +00:00
import2.dir
import4.dir
interface
intrinsic.dir
ken
linkname.dir	cmd/compile: include linknames in export data	2017-02-08 20:59:45 +00:00
method4.dir
safe
stress
syntax	cmd/compile/internal/parser: improved a couple of error messages	2017-02-24 18:54:36 +00:00
uintptrescapes.dir
64bit.go
235.go
alg.go
alias1.go
alias2.go	[dev.typealias] cmd/compile: declare methods after resolving receiver type	2017-01-25 08:04:17 +00:00
alias3.go	[dev.typealias] cmd/compile: export/import test cases for type aliases	2017-01-20 05:55:53 +00:00
alias.go
append.go
args.go
assign1.go
assign.go
atomicload.go
bigalg.go
bigmap.go
blank1.go
blank.go
bom.go
bombad.go
bounds.go
chancap.go
chanlinear.go
char_lit1.go
char_lit.go
checkbce.go	cmd/compile: improve generic rules for BCE based on AND operations.	2017-03-04 16:13:07 +00:00
clearfat.go
closedchan.go
closure1.go
closure2.go
closure.go
cmp6.go
cmp.go
cmplx.go
cmplxdivide1.go
cmplxdivide.c
cmplxdivide.go
complit1.go
complit.go
compos.go
const1.go
const2.go
const3.go
const4.go
const5.go
const6.go
const.go
convert1.go
convert2.go
convert3.go
convert.go
convlit1.go
convlit.go
convT2X.go
copy.go
crlf.go
ddd1.go
ddd2.go
ddd.go
decl.go
declbad.go
defer.go
deferfin.go
deferprint.go
deferprint.out
divide.go
divmod.go
empty.go
env.go
eof1.go
eof.go
errchk
escape2.go	cmd/compile: ignore some dead code during escape analysis	2017-02-27 21:31:04 +00:00
escape2n.go
escape3.go
escape4.go
escape5.go
escape_array.go
escape_because.go
escape_calls.go
escape_closure.go	cmd/compile/internal/syntax: establish principled position information	2017-02-15 01:33:03 +00:00
escape_field.go
escape_iface.go
escape_indir.go
escape_level.go
escape_map.go
escape_param.go
escape_slice.go
escape_struct_param1.go
escape_struct_param2.go
escape_struct_return.go
escape.go
fibo.go
finprofiled.go
float_lit2.go
float_lit3.go
float_lit.go
floatcmp.go
for.go
func1.go
func2.go
func3.go
func4.go
func5.go
func6.go
func7.go
func8.go
func.go
funcdup2.go
funcdup.go
gc1.go
gc2.go
gc.go
gcstring.go
goprint.go
goprint.out
goto.go
heapsampling.go
helloworld.go
helloworld.out
if.go
import1.go
import2.go
import4.go
import5.go	cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests	2017-02-10 01:22:30 +00:00
import6.go	cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests	2017-02-10 01:22:30 +00:00
import.go
index0.go
index1.go
index2.go
index.go
indirect1.go
indirect.go
init1.go
init.go	Revert "cmd/compile: improve error message if init is directly invoked"	2017-03-06 23:48:37 +00:00
initcomma.go
initialize.go
initializerr.go
initloop.go
inline_literal.go	cmd/compile: copy literals when inlining	2017-03-03 21:29:32 +00:00
inline_variadic.go	cmd/compile: generate code that type checks when inlining variadic functions	2016-11-30 19:46:00 +00:00
inline.go
int_lit.go
intcvt.go
intrinsic_atomic.go
intrinsic.go
iota.go
label1.go
label.go
linkmain_run.go
linkmain.go
linkname.go	cmd/compile: include linknames in export data	2017-02-08 20:59:45 +00:00
linkobj.go
linkx_run.go
linkx.go
literal.go
live1.go
live2.go
live_syscall.go
live.go	cmd/compile, runtime: specialize convT2x, don't alloc for zero vals	2017-02-28 19:23:33 +00:00
locklinear.go	test/locklinear: deflake again	2017-03-06 15:05:42 +00:00
loopbce.go	cmd/compile/ssa: more aggressive constant folding	2017-02-28 20:25:33 +00:00
mallocfin.go
map1.go
map.go
maplinear.go
method1.go
method2.go
method3.go
method4.go
method5.go
method.go
named1.go
named.go
nil.go
nilcheck.go
nilptr2.go
nilptr3.go	cmd/compile: re-enable nilcheck removal in same block	2017-02-17 19:19:59 +00:00
nilptr4.go
nilptr.go
nosplit.go	test: add mipsx case to nosplit.go	2016-12-15 22:43:28 +00:00
notinheap2.go
notinheap.go	cmd/compile/internal/gc: inline typedcl0 and typedcl1	2017-02-01 22:52:32 +00:00
nowritebarrier.go
nul1.go
opt_branchlikely.go	cmd/compile: insert scheduling checks on loop backedges	2017-01-09 21:01:29 +00:00
parentype.go
peano.go
phiopt.go
print.go
print.out
printbig.go
printbig.out
prove.go	cmd/compile: use len(s)<=cap(s) to remove more bounds checks	2017-02-02 17:45:58 +00:00
range.go	cmd/compile: fix assignment order in string range loop	2017-02-28 08:23:52 +00:00
recover1.go
recover2.go
recover3.go
recover4.go
recover.go
reflectmethod1.go
reflectmethod2.go
reflectmethod3.go
reflectmethod4.go
rename1.go
rename.go
reorder2.go
reorder.go	cmd/compile: Ensure left-to-right assignment	2017-02-11 21:46:21 +00:00
return.go
rotate0.go
rotate1.go
rotate2.go
rotate3.go
rotate.go
run.go	cmd/compile: insert scheduling checks on loop backedges	2017-01-09 21:01:29 +00:00
rune.go
runtime.go	cmd/compile/internal/gc: separate builtin and real runtime packages	2017-03-01 01:06:32 +00:00
shift1.go
shift2.go
sieve.go
sigchld.go
sigchld.out
simassign.go
sinit_run.go
sinit.go
sizeof.go
slice3.go
slice3err.go
slicecap.go
sliceopt.go
solitaire.go
stack.go
strength.go
string_lit.go
stringrange.go
struct0.go
switch2.go
switch3.go
switch4.go
switch5.go	cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests	2017-02-10 01:22:30 +00:00
switch6.go	cmd/compile: improve error for wrong type in switch	2017-02-02 17:36:43 +00:00
switch.go
tinyfin.go
torture.go
turing.go
typecheck.go
typecheckloop.go
typeswitch1.go
typeswitch2.go	cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests	2017-02-10 01:22:30 +00:00
typeswitch3.go
typeswitch.go
uintptrescapes2.go
uintptrescapes.go
undef.go
utf.go
varerr.go
varinit.go
writebarrier.go	cmd/compile: do not use "oaslit" for global	2017-02-07 17:23:23 +00:00
zerodivide.go	test: lock in test for _ assignment evaluation/zerodivide panic	2016-12-23 17:35:24 +00:00