ld: increase default stack size on Windows for cgo

Fixes #2437.

R=rsc, hectorchu, mattn.jp, alex.brainman, jdpoirier, snaury, n13m3y3r
CC=golang-dev
https://golang.org/cl/5371049

3 files changed, 17 insertions, 2 deletions

diff --git a/src/cmd/ld/lib.c b/src/cmd/ld/lib.c
index 82f3f007f4..5a4d752892 100644
--- a/src/cmd/ld/lib.c
+++ b/src/cmd/ld/lib.c
@@ -274,6 +274,7 @@ loadlib(void)
 	for(i=0; i<libraryp; i++) {
 		if(debug['v'])
 			Bprint(&bso, "%5.2f autolib: %s (from %s)\n", cputime(), library[i].file, library[i].objref);
+		iscgo |= strcmp(library[i].pkg, "runtime/cgo") == 0;
 		objfile(library[i].file, library[i].pkg);
 	}
 	
diff --git a/src/cmd/ld/lib.h b/src/cmd/ld/lib.h
index f66eb438f0..bbaa52d43c 100644
--- a/src/cmd/ld/lib.h
+++ b/src/cmd/ld/lib.h
@@ -125,6 +125,7 @@ EXTERN	int32	nsymbol;
 EXTERN	char*	thestring;
 EXTERN	int	ndynexp;
 EXTERN	int	havedynamic;
+EXTERN	int	iscgo;
 
 EXTERN	Segment	segtext;
 EXTERN	Segment	segdata;
diff --git a/src/cmd/ld/pe.c b/src/cmd/ld/pe.c
index 2e50490cec..1d70b4808b 100644
--- a/src/cmd/ld/pe.c
+++ b/src/cmd/ld/pe.c
@@ -650,8 +650,21 @@ asmbpe(void)
 	// Commit size must be strictly less than reserve
 	// size otherwise reserve will be rounded up to a
 	// larger size, as verified with VMMap.
-	set(SizeOfStackReserve, 0x00010000);
-	set(SizeOfStackCommit, 0x0000ffff);
+
+	// Go code would be OK with 64k stacks, but we need larger stacks for cgo.
+	// That default stack reserve size affects only the main thread,
+	// for other threads we specify stack size in runtime explicitly
+	// (runtime knows whether cgo is enabled or not).
+	// If you change stack reserve sizes here,
+	// change them in runtime/cgo/windows_386/amd64.c as well.
+	if(!iscgo) {
+		set(SizeOfStackReserve, 0x00010000);
+		set(SizeOfStackCommit, 0x0000ffff);
+	} else {
+		set(SizeOfStackReserve, pe64 ? 0x00200000 : 0x00100000);
+		// account for 2 guard pages
+		set(SizeOfStackCommit, (pe64 ? 0x00200000 : 0x00100000) - 0x2000);
+	}
 	set(SizeOfHeapReserve, 0x00100000);
 	set(SizeOfHeapCommit, 0x00001000);
 	set(NumberOfRvaAndSizes, 16);