Fix const function-parameter assertion discovered by fuzzer.
During constant-folding, we baked in an assertion stating that any
const-typed variable reference ought to have an initial value, because
you can't declare a const variable without assigning a value. However,
function parameters are an exception to this rule! They are variable
references and are allowed to be const, but will not have an initial
value. (In this case, `const` just means you can't alter the value.)
In this case, all we needed to do was remove the assertion; we already
treated this case defensively and with the appropriate care.
Change-Id: I61242c6d08c59886c6992898f195771e6334f2b4
Bug: oss-fuzz:37465
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/441239
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/gn/sksl_tests.gni b/gn/sksl_tests.gni
index 0bcd2a9..b39a591 100644
--- a/gn/sksl_tests.gni
+++ b/gn/sksl_tests.gni
@@ -98,6 +98,7 @@
"/sksl/errors/Ossfuzz32587.sksl",
"/sksl/errors/Ossfuzz32851.sksl",
"/sksl/errors/Ossfuzz37457.sksl",
+ "/sksl/errors/Ossfuzz37465.sksl",
"/sksl/errors/OverflowFloatLiteral.sksl",
"/sksl/errors/OverflowIntLiteral.sksl",
"/sksl/errors/OverflowInt64Literal.sksl",
diff --git a/resources/sksl/errors/Ossfuzz37465.sksl b/resources/sksl/errors/Ossfuzz37465.sksl
new file mode 100644
index 0000000..c16257a
--- /dev/null
+++ b/resources/sksl/errors/Ossfuzz37465.sksl
@@ -0,0 +1 @@
+float f(const float x) { 5+x; }
diff --git a/resources/sksl/shared/Functions.sksl b/resources/sksl/shared/Functions.sksl
index d4b5b5f..5386c74 100644
--- a/resources/sksl/shared/Functions.sksl
+++ b/resources/sksl/shared/Functions.sksl
@@ -2,7 +2,7 @@
uniform half4 colorGreen, colorRed;
-float foo(float2 v) {
+float foo(const float2 v) {
return v.x * v.y;
}
diff --git a/src/sksl/SkSLConstantFolder.cpp b/src/sksl/SkSLConstantFolder.cpp
index 50a656d..2048e8c 100644
--- a/src/sksl/SkSLConstantFolder.cpp
+++ b/src/sksl/SkSLConstantFolder.cpp
@@ -213,8 +213,7 @@
}
expr = var.initialValue();
if (!expr) {
- SkDEBUGFAILF("found a const variable without an initial value (%s)",
- var.description().c_str());
+ // Function parameters can be const but won't have an initial value.
break;
}
if (expr->isCompileTimeConstant()) {
diff --git a/tests/sksl/errors/Ossfuzz37465.glsl b/tests/sksl/errors/Ossfuzz37465.glsl
new file mode 100644
index 0000000..561b73d
--- /dev/null
+++ b/tests/sksl/errors/Ossfuzz37465.glsl
@@ -0,0 +1,4 @@
+### Compilation failed:
+
+error: 1: function 'f' can exit without returning a value
+1 error
diff --git a/tests/sksl/shared/Functions.glsl b/tests/sksl/shared/Functions.glsl
index 256fbf7..12f7574 100644
--- a/tests/sksl/shared/Functions.glsl
+++ b/tests/sksl/shared/Functions.glsl
@@ -2,7 +2,7 @@
out vec4 sk_FragColor;
uniform vec4 colorGreen;
uniform vec4 colorRed;
-float foo_ff2(vec2 v) {
+float foo_ff2(const vec2 v) {
return v.x * v.y;
}
void bar_vf(inout float x) {
diff --git a/tests/sksl/shared/Functions.metal b/tests/sksl/shared/Functions.metal
index 1597fef..ee22a09 100644
--- a/tests/sksl/shared/Functions.metal
+++ b/tests/sksl/shared/Functions.metal
@@ -16,7 +16,7 @@
bar_vf(_var0);
x = _var0;
}
-float foo_ff2(float2 v) {
+float foo_ff2(const float2 v) {
return v.x * v.y;
}
void bar_vf(thread float& x) {